I thought about it for a while, played around with that back panel, moving it around to see what various sized openings did to the tone, and decided I'd try a sound port/sound hole. Here's how she looks now.

I also did some more work on the bracing through the back panel access, thinning the tone bars down some more.
I think it sounds pretty good acoustically now. It's not a cannon, and definitely doesn't have the low end boom of a good dread, but it's volume is loud enough that it holds it's own with other acoustic guitars, and it's tone, which is pretty balanced with more of a midrange sound, cuts through well.
I will post a soundclip hopefully some time tommorrow evening, for those of you who might be interested.
It remains to be seen how the soundports will affect feedback through an amp, but since I play in church and am not close to cranking it anyway I've experienced no issues as of yet.