it would be good if you added 1337 coin , ember coin , B3 coin , etc....
Are those really good coins to be added on a gambling site? I have only heard about 1337 coin but as I know it has so low volume and I think it wont worth to add as there might be only small numbers of people who are going to gamble with that altcoins. Better to stick on the most popular altcoins such as ETH, LTC, XMR, etc.
he chose some real crapy coins,you can check them out at coinwarz,the market caps are low
think there wil lbe not much demand outside of the top ten most popular gambling currencies
if you catch the trend,like the early ETH adopter sites,you can get many new players
other than that-have a look at crypto-games and their choice of coins,IMHO the ones needed are all there