See my comments in red above.
I've done a couple of trips like this, now that my dd has 'aged out' of both Disney and going with me. (We did go for a week with her best friend after they turned 21 to do drinks around the world. It was fun, but I actually realized that I prefer the shorter more relaxed trips now.) So I totally get you. Sounds like a perfect trip to me.
Honestly, renting the points for a studio is hard enough to justify financially, so I'd happily sleep on the sofa bed. If it's truly terrible, we've shared a bed before and managed fine- but I'm also one who can sleep just about anywhere!
Good point about hoppers- I figure I'll leave that up to him. You're right that I have them, but I don't want to count on him wanting to pay the up-charge.
As for Day 1, you're right that it's a little light. Partly that's by design, because once I get something in my head I get committed to actually doing it, whether or not it feels like fun in the moment! But practically (partly depending on weather), I could see making that a pool day or going to Downtown Disney (I'm not a shopper, but my friend is). Or starting a MK resort area bar crawl in the late afternoon. I tried to do something like that last trip, after spending the morning and afternoon at the Braves' spring training- but ended up bailing on Trader Sam's after the fireworks because there was still a wait to get in and my feet were killing me. It might have had something to do with being at MK and AK from 7:30am-10pm straight the day before, and then being up before dawn to spend 7am-3pm in the blazing sun at the Wide World of Sports!
I think if we do this, I'd likely make it a priority to take advantage of everything at AKL we'd want to- meaning the animals obviously, but also restaurants, the lounge, even the pool. Firstly because it's not a place I can afford to stay regularly (or at least, not if I want my travel budget to stretch the way I like it to). Also though, because knowing this friend is a cruise person, I know he appreciates being able to walk out the room straight to various activities- and this resort has the potential to be a lot like that. It's also an approach that, by design, would probably have a balance of activity levels.