I never thought I'd be so passionate over a specific TT model or brand, but ever since I purchased my Outback (2 months ago), I just absolutely love this trailer. I've studied the Keystone web site, the Outback floor plans, every nook and crannie about them I can find. We've been on 5 week-end trips and 1- 5 day trip since we purchased it. It handles nice, it's an attractive model, people really notice it at the campgrounds, I get questions all the time. It's comfortable, warm, it has space and functionally works very well.
It has a heated underbelly, all the valves, everything is inside. (It's call Artic Barrier). So far, there is absolutely nothing I do not like about this camper.
The 312 Bunk House is actually the one we really contended about purchasing. When we explained what we were really looking for, the dealer pointed us to the one we finally got (a big difference than a bunk-house, but it really is perfect for us).
What I'm saying is ... I think you will like the Outback and I think it will serve your purposes. I strongly recommend the 2500 or 3500 with a shell over the bed of the truck for the dogs. You can carry your generator back there then too. I have a generator and this arrangement worked quite well.
One thing I would recommend about your floor plan on this model: see if the dealer would swap out that bench style dinette for a free standing table and 4 chairs. A real table and chairs is sooo much nicer, unless you really need the dinette for extra bed space. Then keep the dinette. But if not ... see if they'll swap it out.
I really understand how you feel about the MH and the 5er, towing a car, and space in the MH. We struggled with these same issues and we no longer have kids at home. Our kids are grown and no longer camp with us, and the grand kids are too far from us now too. The dealer really pointed out ... why do you need bunks when no one will be using them.... he was right too. We've been so acclimated having kids, we never considered what floor plan would actually work and is really comfortable for only 2 people 99.999% of the time! So we went with the 298RE model and it really was the right decision. Sounds like you've made up your mind too ..... my blessings on the Outback! You won't be disappointed.
Very nice floor plan there: