Observe the other casinos offering rewards and by that, you can make come up with an idea of what the lacks bonuses that don't have yet and modify those to become better so the gamblers make it into your casino, for the active gambler it is ideal to have the top wagers or the top players with a lot of wins and losses as a consolation prize of playing too and spending a lot of money, next is there's a community vote that allowing the chat box vote for their best gambler they idolize and after that, you can have a top in the voting makes a free spin.
Some casinos create a weekly and monthly competition for the highest wagers and most active players and reward them with either free spins or good amount o crypto. It makes betting more exciting, especially for high rollers and bettors. They also reward free spins for players who stay active on their chat community which could keep the interactions on their chat box more alive. You can visit reputable casinos to get more ideas.
I believe that this could be effective since there are many casino that are doing this and I see that many gamblers are trying to win those small tournaments by wagering more which is helpful to the casino. Though, High rollers are the one who are most likely winning on those tournaments especially those long ones (weekly,monthly). Small time gamblers do have chances in hourly and daily which also makes them play even if they do not have high balances. A good chat traffic should be there 'always' since I believe that it represent the activeness of the casino community, Also it's fun to chat with fellow gamblers.