Love that you are branching out to the World! We are DLR veterans ourselves & did our first trip to WDW last spring. DLR will always be home, but we are itching to get back to WDW, hopefully one of these years soon...
As for your overall plans, right off the bat, no park hoppers necessary! Especially for a first time trip working on getting your bearings, etc. You're also doing the drinking right with your arrival monorail bar crawl plans & going an extra day to Epcot.
As for the details:
Day 1- For your arrival day, even though WL would be an easy boat ride away from the C and the Christmas decor might be very lovely, I tend to agree with you that you will be more apt to get back to Poly & get some rest, but definitely play it by ear. IF you can get your Celebration at the Top ADR for Sunday night rather than Wed night, I feel like Sunday might be a better option to boat over to WL after your rest/non-park day. Also an option, if you really want a low-key day arrival day book Ohana this night and really get some rest and enjoy the resort you will be calling home for the week. But then you would be putting the monorail bar crawl on a different day (maybe on Wed instead of Cali Grill - this is again assuming you get Celebration at the Top Sunday night instead of Wed- If do the bar crawl Wed, then you would then prob want to sleep in the next day and do a late-start at MK which might not be bad esp if you have a dinner ADR at BOG making a midday break a bit complicated- at least it did for us in planning. Late MK start with using the BOG ADR as a break in the middle to rest your feet would also help you to stay & close the park down with the Kiss Goodnight- one of my favorite moments in MK was when we ended up staying until this moment, being on Main Street slowly meandering out and having the Kiss Goodnight send us out the front gates. You can even then late start AK the next day with a similar plan with Sanaa early dinner as your sit-down ADR to close out AK).
Day 2- I think regardless of the rest you do/do not get planning a late start to Epcot is perfect for your body clocks. We found coming from West to East that rope drop, even 9am rope drop was brutal. Illuminations definitely didn't need a FP when we went, but with it being a very busy weekend, I wonder if that changes the game here? Not sure, but I definitely would rather use my Tier 1 FPP for Test Track or Soarin (Frozen wasn't there last year, so I have no idea on that..). Maybe if there are any Tier 1's left after you've used your 3 FPP's?
Day 3- We didn't look into much at Downtown Disney, but we definitely could have spent so much more time there. We did it on a night after AK (when it closed at like 6pm). It definitely wasn't as restful as I'd envisioned but I think it's because we were cramming it into a 3-4 hr block after a day at the parks, so a day dedicated to it seems much more restful. The more I think about your overall plans, the more I love the idea of you coming back to the hotel later afternoon, resting up a bit then having this be your night to go to the Contemporary with the Celebration at the Top and fitting in a trip over to WL to take in the Christmas decor. Sounds like a lovely rest day to me. But crucial to it is snagging that Celebration at the Top ADR for this night.
Day 4- We didn't do any dining at HS so I can't comment on anything there, but we did F! at HS (after many times of loving Disneyland's F!). I would 100% prioritize Star Wars FWs over F! The best part about it for us was that there was a seat! It was nice to get to see the show, but it didn't quite compare to seeing F! on the Rivers of America. We also did the later showing so it wasn't as crazy getting a spot or getting out aftewards & it does seem like the earlier showing, even though there is a seat, requires some camping out/a FP & entails a large cluster of folks trying to get out afterwards.
Day 5- I agree that 5 is your best bet for your ADR. It will help you fuel up for the party & avoid the most crowded time where both party guests and reg ticketed guests can be in. Also, yes you can get 3 FPPs with your party tickets.
Day 6- You'll have to choose either Soarin or Test Track for FPP but since you have 2 Epcot days, do one for each of your Epcot days. Test Track does also have a single rider line and if you can make it to RD for Epcot this day then FP the one (Soarin) and RD the other (Test Track) is how I would do it. Also, I have to agree with the advice that there is SO much good food to eat at Epcot that I wouldn't plan to go eat somewhere else. We made that mistake (well really we had made our ADRs at 180 days out and then at 70 days had to re-arrange a bunch of stuff when the family we were going with had to change some of their plans- so we ended up with Ohana at the end of our Epcot day and I felt like we severely cut short our Epcot time by doing so and also impeded our ability to fully enjoy all the amazing eats/drinks at Epcot). The one bonus you do have is that Ohana is in your hotel so you can make a pretty late Ohana ADR and then just go to bed right after. We had to figure out how to get back to our resort afterwards on top of feeling like we had just cut out some much-wanted Epcot time to make it to our ADR. That being said, we were sat at a table in the very corner of the restaurant with the best view of the castle and Wishes came on near the end of our meal for us to enjoy that amazing view. It was one of my favorite experiences of the whole trip BUT I still would have loved to do it on a night when I wasn't sacrificing Epcot time (maybe HS or MK time, but not Epcot).
Day 7- Definitely love your plan for BOG dinner. Putting it near the end of your trip gives you a great opportunity to get a decent time for eating. As for targeting what's different at MK: Splash to me is also different/better at WDW so make sure to add that to your list, also PeopleMover. Riding it at night was my favorite MK attraction. I also really enjoyed Mickey's PhilharMagic that you have on there (but you definitely don't need a FP for it) & Seven Dwarfs was good (but definitely overhyped). Space I dislike at WDW- seems jerkier than our DL version but I do miss the classic music since we've had so much Hyperspace, so next time I might not mind it as much if we still haven't had classic Space back to DL by then. I also really enjoyed all the extra space in Adventureland that we just don't have in DLR. We never made it to Tiki Room or Pirates, but we did do Jungle Cruise and I LOVED it at WDW where at DLR it's something that I can take or leave on any given trip. I also loved the Swiss Family Roberts Treehouse which was a surprise because I do dearly love Tarzan's Treehouse at DLR and hadn't even planned the treehouse, my son just really wanted to go see what it looked like & it was something he could do with just me while my hubby relaxed in some shade & took a break with our daughter who was sleeping in the stroller. We also got really into the Sorcerer's of the Magic Kingdom game & wished that DLR had more types of events like this. Anytime they do a scavenger hunt now we get excited because it kind of reminds us of the game & we really loved going to the different portals around the park and continuing the adventure with our cards.
Day 8- I think Sanaa can still work, but you may not be able do everything in AK. We spent two full days there but our second day from rope drop to close was fully devoted to Wilderness Explorer Badges (except for one ride on the Safari, a lunch ADR at Tusker & watching Finding Nemo: the Musical). We even had FPPs for Dino & EE that we let fall by the wayside because we were so focused on completing all the badges (we & the family we were with had decided to have the kids all dress up together in matching outfits one day and our pick was as Wilderness Explorers as so we went all out for it- have a bunch of great memories but I don't think we'll ever devote that much touring time again to it on a subsequent trip). I feel like without this activity it would have been easy to plan & execute AK in one day. Maybe it'll be different with Pandora & ROL?? But we personally LOVED AK because A) it's so different than anything we have at DLR B) Had a lot of our favorite things from the trip including the Wilderness Explorer Badges, Expedition Everest, Tusker House, Finding Nemo: The Musical, the Safari & my kids LOVED the Boneyard and C) The Tree of Life & the beauty around the park was just so breathtaking and immersive and I actually felt like I rushed through the park even with 2 full days. I am sure that Pandora fits seamlessly into that & I can't wait to go back to see how it does. Anywho, that being said, I realize it's not for everyone, but that's why I also think that Sanaa will still work in your plans (I really wanted to work in either Boma or Sanaa but we just had so many other ADRs that we chose & Tusker House was one of them for the characters for our kids so we skipped out on going to AKL).
Day 9- So I kid you not that our Day 9 was exactly like you have planned. We had 8 park days (we did a red-eye and went right to the parks running our Day 1) and then our Day 9 I decided I didn't want to stress about doing things and making it to the airport for a flight so our only plan was a 10:30 ADR at 1900 Park Fare (for me it was Mary Poppins & Pooh that I just had to see). It was a glorious leaving day. We got to wake up leisurely and have ample time to get everything packed and to the luggage check-in at the resort before taking a bus to MK & then a boat from MK to GF (you will just have a short monorail over so even better for you). We didn't have to be back at the resort for our Magical Express pick-up until about 1-2pm and so we rode the monorail around and said goodbye to all the monorail resorts, ended up at the TC &C thinking we could take a bus back to our resort (we could not) so took the ferry from TC &C to MK to catch a bus, but ended up really enjoying all that exploring time to say goodbye. Even though we could have easily done a last half-day of MK or Epcot and had things we wanted to do, I didn't at all regret not going into the parks. If you still haven't seen the WL decorations or want to try any spots you didn't hit on your initial bar crawl, this day/afternoon might be a fantastic place to fit it in.
Anyway, overall, love the plans and excited to see how you end up deciding with the choices you have in front of you!!!