PvP Games is a good idea, but some casinos that provide this game don't get many players interested in trying it, maybe because opponents are not always available because this is what I have experienced when playing games on mobile applications, sometimes there are no players available to play with, but from all that, I hope that your game development can run smoothly and provide something different from other casinos so that there will be many players who are interested in playing
If so, the OP can still add casino games in general so gamblers can keep playing them if they don't want to play PvP games. What's important is if OP can provide something different from other casinos and inspire curiosity in the players, they will come back to try their luck. And don't forget to do promotions because that will make many visitors come to the casino. Maybe allocating some funds for the promotion and planning how long the promotion will last will let them know how the casino site is developing over time.