why not have a 2v2 ctf? i know when i play 2v2 ctf its fun but i would love to see it in twl. i think it would be an awesome addition to the already great ladder.
also some teams have enough for 5v5 ctf and are on it but want something else to do to fill in the time. you may have 2 5v5 matches a week at max so theres a lot of time in between.
In my honest opinion, Rat Race is an extremely limiting and a little to large for a 2 v 2 CTF map without vehicles. Good maps would be Blood Gulch (as always), Battle Creek, Wizard, Chill Out, and Longest.