There are going to be four main players as far as you are concerned.
1. Ford Galaxy - Sister car to the SMAX, but bigger and visually more MPV like.
2. Chrysler Voyager - Big full sized US MPV.
3. Renault Espace / Grand Espace - As you've already found out, good all rounder.
4. Kia Sedona - Budget MPV, not a great drive but spacious.
Another left field choice if something more van based and "Full Sized" lights your candle, would be a VW Caravelle?!?!
The only way is to go and play, then you will find what ticks the right boxes for you.
Best of luck.