Depends to our taste what we want to use coins. Stratis is potential coin so I don't see any problems to add that.
I don't think adding altcoins increases a casinos popularity, especially right now when BTC fees are low. Basically coins like ETH or LTC are fine but adding niche type of tokens is really unncessary since most of those tokens have no utility except speculation by day traders. These tokens maybe would play a roll if BTC had a huge back log like it did in January 2018, because I remember having to pay $50 to send a single transaction and it still took 12 hours to confirm.
The one token that really should be added to gambling sites is a stablecoin, especially since BTC is so volatile. However due to regulations most casinos don't want to touch tether or any type of regulated stablecoins due to fear of government intervention.