I think $250,000 is a very reasonable target - especially by today's already established Kickstarter standards - and I also don't see anything wrong in principle with money being what ultimately motivates a person to finish a protracted project for which that initial enthusiasm is presumably long gone by now.
For what it's worth, aside from the purely technical aspects (sound quality etc.) the IndieGogo campaign video is by far the best Kickstarter-esque presentation I've seen so far. Blakemore's pitch perfect balance between silly hyperbole and self-deprecating humor is in an entirely different league than (for example) Wasteland 2's cringe-worthy and curiously ill-tempered satire of mainstream publishers, and the actual gameplay content shown is of course unmatched by all those campaigns for as-of-yet-developed games.
I have no idea whether it's realistic to get the game in its current state (whatever that actually is) to polished product in 6 months, but I'm definitely on board for the IndieGoGo campaign. That said, conventional pre-orders would have been vastly preferable to crowdfunding, which depends on exactly the kind of goodwill a guy like Cleve Blakemore is pathologically incapable of building up…