What do you guys think about this? Can this be played over the net? It's very cool stuff.
I can only choose 3 characters, is there a way to unlock other characters?

Yes, there is netplay. Not sure where you can find opponents - possibly one of the Higurashi related IRC channels like #windfs or #hinamizawaclub on Rizon.

To unlock more characters, beat some of the story modes, I think.

fuckers don't even bump this because they lack the foreign language skill to dl this. sad sad sad.