integrating lightining and other smaller altcoins could be two interesting ways to go to improve the website too.
Adding more altcoins can be good but only if they are in demand and fees is not too high as well the liquidity factors also need to be kept in mind so that users don't face any problems while for lightning network the demand is good and network has capacity also now.
Well, honestly from my personal opinion, I will have to agree with you first, but then, what i think is most important is integrating the bitcoin lightening network for faster and cheaper transactions and fees, adding more altcoins is indeed a good thing as it gives users, most especially those with not with not very deep pockets, the option to deposit and play with which ever coins they already have at hand without having to pay fees converting them to bitcoin and also paying fees to withdraw the bitcoin to the casino for playing, but whatever altcoin that is being added must be in the top 50s or 60s according to coin market capitalization, so yeah, I support that any altcoin being added must be one that is popular and people make use of, not one that will become dormant and possibly face liquidity issues.