Okay, I looked further, and did find some posts that were similar in nature to mine (don't know how I didn't see them the first time). But while they were similar, they weren't the same. After reading those posts, I am thinking I need to split this into two questions:
1. Is it possible, without too much customization, to get the user_level and user_login information prior to the wp_start() command? With that information, I think I could limit things the way I am trying to - the way I did in b2.
2. Or, if that is too much modification, is it possible to remove the ability to post for user_levels other than, say, '9'?
Actually, I think those are both things I would like to make happen. My blog is an "only me" post blog, with only comments permitted by others, and like in the original post, I have the "general" category for everyone, one additional category (two total) for the next level user, and then all categories for all other levels, all without the ability to post.
Anyone have any ideas, or places to look? Thanks!