Thanks for the honest review! As for not agreeing with stuff, that's okay as long as you still like the rest! I read plenty of VNs whose philosophies I may not agree with, but get what it's going for. So long as it doesn't seem like I'm trying to push it down anyone's throat!
Gabe does seem to come across as a blank slate, but that's part of the intention. He's a weak Catholic, but that might not be apparent to most people at first glance. I also need him to be somewhere in the middle to able to relate to the wide variety of interests such as gaming to basketball and martial arts, etc. I'm sure there's room for me to do better at least.
It's a shame you don't like the music. That's one of my favorite things to direct musicians on. It could be that it's too safe, but I made sure to put in examples similar to other works that I enjoyed to make sure to fit the themes for different directions of the game. Maybe once I get unique character themes in, it'll have more personality?
I'd highly recommend Earthsea as LeGuin has been a great fantasy author. I'm sure I would like Ender series and perhaps Atwood.
Hope to hear more opinions when you and your friend finish!