It has potential, I'll give it that. I'm interrested to see what you do with it. I understand you don't want to go too crazy on labor, but I don't think you will really need to. If you do put in some time, I certainly think it will be worth it, and pretty inexpensive compared with getting a prebuilt case of the same quality. So I say, go for it! If it doesn't turn out to your satisfaction, the cost is minimal, so that's good. I'm actually kind of jealous, I've been looking for a preject case to work with for less than $20, really just for fun, but have had no luck.
I like TLHarrell's sugestions, especially moving the PSU. Removing the 5.25" bay rack should give you ample space up front. It looks like a rather large mid-tower, so with those bays removed you shouldn't have too much of an issue with W/C.
One of the first things I'd do in planning is figuring out your plan for cable management. You said it pretty much non-existant, but if you want this case to really shine, you'll want to come up with a good way to compensate.
Have you thought of a side panel idea, or if you will window it?
Also, what were you thinking on collors? Make sure you paint that interrior once you get your layout set up, to give it that nice finished look!
I'm looking forward to see what you do with it, maybe you can get some good ideas for me too!
EDIT: I cant see the inside top in your pictures, but have you considered (or have the access to tools) a top cut-out for additional exhaust? It might be a decent idea, since you plan on pulling so much air fromt he front of the case. Perhaps you'd have room to mount a 360 rad there? That may be a little to much work though...
Edited by Purger - 11/8/12 at 10:49am