AKL is my favorite DVC resort, but I've done split-stays at BLT for the last trip, and this upcoming one as well, and BLT has become my second-favorite resort. How either on would work for you all comes down to preferences.
BLT has the convenience of walking to MK and monorail or boat access to all of the dining and entertainment options of the MK-area resorts. The decor is very contemporary and slick, and the Mickey touches are subtle. The biggest down side IMO, is that the studios are kind of small.
AKL studios are more spacious. The decor is warm and well-themed, with loads of dark-stained carved wood, and the like. The biggest draw here is the animals, and there are plenty of viewing points throughout the resort. I am also
in love with the lobby at AKL-Jambo House, and before I got DVC would carve a couple of hours out of my vaction to come over to AKL and just relax in that lobby (usually before a good dinner at Boma). The dining options at AKL are not extensive, but they are excellent. I love Boma for both dinner and breakfast, and I think that Sanaa is the best casual TS on property.
As much as I love having all that fantastic dining (and drinking
) readily available at BLT, for me personally, the Feel of AKL wins out. YMMV.