Just some points to remember
1) Do not let the developers have access to provably fair, or similar feature of the site. MD was screwed this way because their devs knew the seed generation/could access the adminstration.
2) Be sure to have at least 20 BTC when making a gambling site, if not, you're going to have a hard time making profits
3) Be sure to make it provably fair, anything else(except softswiss etc, but a you said, you need a new idea) might be considered rigged and when the complaints later come, you have no way of proving the site is not rigged
Good luck
As I understand it, 20 BTC startup wil not be enough.
You would need much more than 20 BTC, as I understand that you need to get a license to run a gambling site in most jurisdictions. This means, you must go to court in order to get your licence: you need a good solicitor too to sell your case, otherwise you are acting illegally to create a site without a licence that envolves gambling.
20 BTC is not enough but why does he need a license? did he mention that he wants to open a fiat casino? this is a bitcoin forum and I would assume that he meant a bitcoin game. Op please correct me if I am wrong