RTBs are typically extremely docile snakes. Nicer than many BPs. However, there are exceptions.

No red tail could possibly eat a human.. lol I don't count them as a dangerous snake.

10' for a colombian red tail is quite unusual. 8' is more average.

I don't think you would need two people to handle it. If it is an aggressive snake, it may be a good idea, but we are not talking about a 20' snake here.

Jumbo rats will probably be fine, but you may need to feed more than one, vs one small rabbit.

55 gallon? no.. 75.. no. You need a nice 4' cage now, then 6' when she grows a bit more.