He sleeps inside with me. Sometimes I soooo wish he'd sleep in the vestibule, but as I said he likes to crawl under any opening, which of course he doesn't even remotely fit, so that means he pulls stakes out and disaster ensues.
As for the frameless pack, that is a tough one because there is skill involved in packing it, and depending on what you are carrying it might not carry as well. I use the Gossamer Gear Gorilla...which has a removable frame so I get the best of both! It is by far my favorite pack. I also used a circuit on the JMT this year and it was fine, but I still like the gorilla better.
Packs are like shoes though, and fit is very, very personal. And most of these packs you can resell here on gear swap, so go with what you feel most comfortable with, but be ready to swap out if its not great. The cottage gear guys make great stuff, and you'll be able to get rid of whatever you don't like with not too much cost. And you'll learn what works and what doesn't. That's important as you hone your skills.....