Yes- time based at different times of the year- usually during value season is when you will get the largest discounts. Different deluxe resorts have different discounts- we usually just go with the resort with the best percent discount the week we are going over- but we live here so aren’t too picky about location. We have done well at AK- got 35% on a CL savanna view room a couple of years ago.
Looks like you have a younger child. That indicates you will be spending most of your time at the MK. Years ago we got 35% at the Poly- haven’t seen that level of discount recently, though. Not sure about discounts at the other monorail/MK resorts recently since they are rarely the best discount level. Just plan your trip in value season during the slower times of the year and hopefully the stars will align for you.
DVC will save you money over an AP in a studio- but that’s about it. Larger families can do well renting DVC as well. IMHO a normal size family that will need something beyond a studio will do better with the AP discount. Remember- this is one person’s admission as well, so it is going to be hard to offset one person’s admission with a DVC rental over an AP discount. So in other words, with a DVC rental you will have the rental cost- then pay admission for the person that would have had an annual pass on top of that.
Also, look at getting a Chase Visa card. Sometimes cardholders get rates as good as AP or FL resident rates- but it is inconsistent. There is no annual fee, so it’s worth carrying one even if you don’t use it a lot. They have had some decent discounts over the years.
Lastly, do your research and learn about this stuff so it’s second nature to you. Join some other fan sites like the DisBoards in addition to this board. They have a really active budget board (I post there regularly). There are unique and interesting ways to save money for your trip using gift cards and gathering points for flights using credit cards. You have a lot of time- and the amount of available information is overwhelming. Take your time, learn some of the budget tips- and you will get back to WDW before you know it.