Congratz! Personally I just killed him once for the reward and then quit again. Gonna wait for the actual release so I can actually earn stuff by hunting.
That's not a bad idea, you don't get exhausted or anything if you wait for the actual release to hunt more. Beta is pretty good for getting used to monsters movesets/ patterns.
Yeah, Monster Hunter is great when you're actively working towards something, but I always tend to burn out whenever I end up hunting something just for the sake of it or for some gear I know I'll pretty much never use.