Triplefigs, my Dad and I stayed in a TPV during our October 2007 Trip. Our room was one of the hammerhead rooms and was in Big Pine Key. I thought we had a really great view. There was one low hanging branch that slightly obstructed the castle, but a slight duck made it a non issue, and for kids it would be no big deal. From the balcony we could also see the MK monorail station and the monoraial track over seven seas lagoon (for your son!), the castle, MK train station, astro orbiter and space mountain, and the contemporary, depending which way you looked. We had a GREAT view of EWP here too.
From the other balcony, you could see the Poly and the WP.
The room was nice, lots of room, the real table and chairs still in the room, quiet, and clean (no smoke residue AT ALL even though this used to be a smoking room. As I am very allergic, I would have noticed). It was a first floor room. Okay, I just looked it up on the old thread where I had posted about my stay, and it was room 9147.
I hope your trip works out for you this time