I gotta agree with the Bird of prey/battlecruiser similarity.
However I also think it looks a bit like the drone kamikazi ships from the Star-Wars Books.
The very large front end is nothing but armor plating, give it a bunch of under-powered cannons so the ship actually -looks- like an important cruiser/destroyer/freighter at least...
Let a heavy cruiser or battle ship come close and the thing will turn around, let the nose (where it has a lot of armor and mass) swing around, fire up the engines and kiss that cruiser goodbye.
But at any rate for it's own merit, a missle cruiser sounds REALLY good to me. That front end would be a logical (kinda) place to put a bunch of launchers and their payloads. The rest of the ship has that long bow to keep them relatively away from any unexpected explosions, maybe give them time to hit the escape pods.