I would think that splitting your stay might be the route to go staying at AKL at the end. The pool area and slides at the BC/YC are really appealing to older kids plus you have the activity at the Boardwalk in the evening time. The only drawback, for us, is the lack of a "food court" environment at the BC in the AMs. Waiting in line at Beaches and Cream isn't appealing...but the pool bar is nice during the day. The rooms at the BC/YC are bigger than the AKL so that might be a nice change for you...and if you get the view of the lagoon area there is lots of activity to sit and watch.
We have done split stays and it is very easy. They transfer your luggage for you and everything. We check call bell services to pick up our luggage, and then check out of the resort ... spend time in the park and go back and check in at our new resort mid afternoon. The luggage arrives later afternoon ... but when we check in we call and ask bell services if it is there or not. If it is, they deliver it to the room. If not, you just call back in a bit and check with them. They will deliver the luggage right to the room. We've never had a problem with the transfer. Very easy. The only drawback is we tip when we they pick it up at the one resort and tip again when they deliver it to the room ... but for me, I don't mind ... afterall I appreciate someone else handling it for me so it is well worth it.