Welcome to the forums!
I think you have the right idea of larger is better. I am partial to the 34' triple axle. While I am not full timing, I would definitely look at what your needs will be in regards to storage. Even the big ones can get small in a hurry with too much "stuff". In my rig everything has a place and every place has a thing. I tow with an excursion, so I have good storage in the back for bulky items/ odds and ends.
One thing I like about my 34' is the hallway separation between the front and rear bedroom. I have two hall partitions that allow me to close off the back if the little ones are sleeping or napping or the DW needs some privacy. (there is also a large ~5' hall wardrobe closet in the 34'....great storage)
If you find a rear bath model (31' model), pay attention to rear sag. there are several threads on here regarding this condition. If you are camping in the south during the summer, you may want to consider the upgrade to dual A/C's as well. not required, but would make it a little more comfortable in the summer!
Good luck on your search!
1982 34' Limited
2000 Excursion V10 4x4