The only point in selecting an order as an RCA bidding is if there is more than one vacant route. Then you should select which routes you prefer, in order, including all the routes the regulars have that aren't up for bid, just in case they bid on one of the vacant routes.
If you are the only RCA bidding you will get whichever route is left over.
An RCA in my office didn't want a route so he let it skip over him. Then, wouldn't you know it, the RCA who bid on that route bid off it next time and he got the route he didn't want anyway. Moral of the story, always go regular, you can select your route later when you have more seniority.