Not sure of ages. I always pick 1 bedrooms over studios, but we want the full kitchen and washer/dryer, etc. Also at AKL you get 2 bathrooms in a 1 bedroom. Plus I love AKL as a resort, except for the travel time to parks
Poly is good for a studio, but depending on ages, could be cramped in 1. but close to MK. When we've stayed there, we've almost always just taken the monorail from the TTC/not the lobby. Pool is nice.
saratoga is always one of my last choices, due to all the bus stops, and not being able to walk to any parks, but if you are going to D Springs a lot, or don't always plan to use the bus. could be an option, and if you want the privacy of 2 studios, then that would be a good choice.