[[:Category:User Guides]]...good idea or bad?

No. I'd rather have it kept in separate pages and yes, they will have to be subpage(s) of the user just as a way to know who wrote it and such. Fortunately, I am fine with anyone editing and correcting my mistakes, provided there was a given reason and I approve of it. I'll leave it up to the user if they want people editing their page(s) or not.

Of course, the title will have to be straight forward in order to make finding the guide much easier. I mean "Finale Guide" could mean anything unless someone puts like "G1 Finale" or something like that. Same thing with stuff like guides to skill sets. The name of the guide will have to be something simple and short, but still reflect the guide's content.