always worth to try , nothing business have a free-risk. so far i didn't yet see there is bitcoin gambling site closed due to bankruptcy or something similar. most of them in profit especially a -EV games , no wonder there is very few games based on player vs player , would you take this challenge? to open a PvP game like PvP blackjack? goodluck btw.
you got the point and Try + test = achieving this is what i think that should do first yeah theres a risk and you will not know if this project could be profitable or not.. since the other business there are started and the other business was not successful they are close but the other business here are still alive and active that i think they are really making a good profit..