It depends on how you'd approach the project: if you'd enjoy doing it, go for it - you may find you'll end up with just what you want, with a personal investment in the process and instrument at the end, which can be very rewarding. I've modded several basses now, and I've found it's addictive: off-the-shelf cookie-cutter basses don't interest me all that much these days.
If you're building it to sell, fair enough, you'll never recoup your money, but if you're going to start considering your hourly rate doing something you like, I'd suggest that's massively missing the point.
Oh, and if you buy a Gibson, you might want to look at changing the bridge for a much superior Hipshot Supertone...and that's how it starts...