Moida worked a long time on BitVegas and didn't release the first version until it was really done. He worked hard on security and the backend server, so you (and the people who will be working with you) will have to invest a lot of time and money into it before you can even think about profits or even releasing it to public. Bugs will be exploited
I would like to remind you that BitVegas was slowly losing it's bankroll. Moida said that we had to attract bigger players, so that we could regain what we lost from the faucet (because well, newbs don't deposit). However, we had a big enough bankroll to keep going for quite a while (months, if not years), so I doubt that the lack of money is the reason why BitVegas suddenly stopped.
I don't think security is as big of an issue as you think; bugs in the software are though. If you implement a system where everything is logged and manual verification is required for cashing out a certain amount in a certain time frame, you should be able to catch many people exploiting bugs. Obviously security audits are a must as well, but can be mostly automated.
I think overall the bankroll problem could be solved by moving people away from playing against the house, and having more games where players play against each other with a house rake. A house edge is useful only with a large number of bets over a long time, whereas a rake ensures a steady amount of income.