Most models that I've seen with the separate sofa and dinette in the same slide (even the "super" slides seem to have similar sized sofas... none of which look like they could accommodate stretching out on for a nap.
Some manufacturers offer a "mega lounge" or similar named arrangement. In these, there is not a separate couch and dinette - instead, it is one large seating surface, like a large u-shaped couch with places that you can insert or remove dining tables.
I have a 2013 Cruiser Viewfinder 28BHSS that has this arrangement. Some people love it, some hate it and some have never seen/tried it. Personally, I love it. Its very flexible for various situations, including stretching out for a nap.
You may have to look pretty hard for this layout as I am not seeejng it very much. Not even sure if its a standard offering in the Viewfinders now.
By the way, the Viewfinder 28BHSS is a double/double bunk model, not a true bunk "house" with the separate hunk room and bunks on both sides. Works well for my 2 kids and the occasoonal friend but might not be ideal for those with 3+ kids of their own all the time.
Good luck, Dean