I wouldn't consider a pool home excessive for a family of 4. Shoot, my DH & I like to stay in a condo or suite when we travel with just the two of us. We feel claustrophobic in a standard room - so my opinion is biased.
In some cases, you can get a pool home for about the same money, or just slightly more than the 3-4 bedroom townhomes. The townhomes a WH are HUGE and beautiful by all accounts- not all that different in actual square footage when compared to some of the smaller 3/4 bedroom homes available.
It seems that you've decided on a private pool already. Now you just need to decide how big you want the pool, and if you also want a hot tub at the villa.
Either way your family is going to have a fantastic trip. Both choices will be wonderful and spoiling.
Lisa