I am in the off property camp but that is mostly to be able to get in more trips. Plus we never schedule any downtime in the hotel/pools so really the room is just a place to crash and the DLR onsite hotels are quite a premium when we will be spending all our waking hours in the parks AND most of the offsite hotels we frequent are much closer than DLH or PPH and with younger kids it has been so convenient to roll out and 6 minutes later be in the respite of our hotel room away from crowds and in the AC.
However, the 2 trips we have done onsite stays once each to DLH and PPH have been full of magic. The DLH is definitely my favorite for the history & grounds. The Grand Californian’s location just can’t be beat and the lobby is astounding but bc of the astronomical price, we’ve never been able to convince ourselves to splurge. The PPH can be a mixed bag. There isn’t much to the hotel in the way of restaurants and nothing in the way of any kind of grounds (the pool is on a rooftop on the 3rd floor & everything around it is a parking lot or a busy road), plus the elevators can be a nightmare if staying on a lower floor.
However, our one PPH stay was in a theme park room and at check-in we were upgraded to a 1 bedroom suite on the 10th floor. The VIP feel of having that room and the gorgeous view of the pier in DCA was worth every dollar. We watched WOC in our pjs eating popcorn we’d bought on our way out of the park and when we stayed it was one of the last runDisney events in DLR and we awoke to the pier lit up & rides running (empty) for the racers who were out on the course already & it was just more magic.
So in sum, if in budget, spring for the on-site magic. But if you need to be more budget conscious then there are many great offsite recommendations I can give. Regardless of onsite or off I would NOT try to come in from LA but would make sure you were somewhere in walking distance. Parking at DLR is a bit of a mad-house & only expected to be compounded with the opening of SWGE at the end of this week with no relief coming until the new parking structure is completed (but not expected until July).