When you stand up acoustic in front of an audience, you really are a man without any clothes on. And that can be fun - it depends how much of an exhibitionist you are, I suppose. I quite enjoy it.
I think it's absolutely possible to write a song and go somewhere where no one's been before, uncharted territory. In terms of content, I see limitations where there should be none. I know there are things I wouldn't write about, but that shouldn't be the case. You should be able to make a song out of anything, out of any situation.
Sitting around home I mostly play acoustic. I've got seven or eight guitars of various sorts, including a baritone. Sometimes at home, because a guitar is just lying around, that's the guitar I pick up rather than actually choosing something. I try to plan ahead for my laziness by leaving interesting things scattered about. If I leave a baritone guitar lying around, that's the one I'll pick up, and I'll start writing baritoney things.