You're in luck with the trailer wish list, because every manufacturer out there makes a 24-28 ft bunk model with a queen bed! That's the good news
The bad news is.... every single manufacturer out there makes a 24-28ft bunk model with a queen bed.... which means you'll get burned out in a hurry looking at countless floor plans that all seem to run together.
Take a trip to an RV show, it will help you narrow down what's out there. My cousin and I each have a TT, both our trailers meet your requirements, yet our 2 trailers are very very different.
With your limited wish list, you may be able to find everything you need in a smaller (24ft) trailer. Which could open up the half ton crew can truck market for you. Some of the newer crew cabs have cavernous rear seats, enough for any size car seat to fit.
The full sized 1 ton van idea isn't a bad idea to explore, be warned though, I've never driven a full sized van that isn't extremely crude. They ride and drive terrible. I know, I drive them for work every day.
