Rather than focusing on "oh, no, they're going to say my idea isn't ideal" why not take advice from people who have actual experience? At this point, though, you might as well put those tweeters in the sun visors, since you're abandoning all reasoning relating to speaker installation.
Your biggest drawback on your install is your attitude and unwillingness to take advice. You might end up happy with the way it sounds, because you have no idea how it COULD sound. Rest assured, though, if you'd taken advice from day 1, you'd have ended up with a better system that cost you less.