Those are the most popular and used cryptocurrencies, but those are also the most expensive for transaction fees. Sometimes it takes a long time to get network confirmations. So few players try to avoid the transaction fees and also don't want to waste their time by waiting for the network confirmation. I know livecaino credit deposits even with zero confirmation. Still, It depends on users' choice. So, If you can enable weekly rebates with every available coin, it will be great.