it might be more useful if the odds reflected the odds of winning (including getting 11) rather than the odds of winning that number outright.
ex.: for an individual number or sign, the odds of winning are 1:13. 26 numbers, and you win on 11 or the number. Which means the casino advantage is lowest, oddly enough, on 11.
red, black, low, high, odd, and even have odds of 11/26
and the odds of winning the 'green' bet is 3/13
Casino advantage (the average amount you lose on a bet, lower is better) is as follows
11: 1/26
individual sign/number: 1/13
Green: 1/13
red/black/odd/even/low/high: 2/13