Fans of every AAC program seem to think their school would benefit the Big 12 the most.
The Big 12 isn't looking for a program that has "more potential for growth". More potential than whom? BYU? Houston? Memphis? Connecticut? USF? Cincinnati? With the exception of Memphis and BYU, every school I've listed beat UCF, some even curb stomped UCF at Bright House Networks Stadium for God's sake.
Right now your program is crap (0-12, 0-8 AAC) and it will most likely be crap for some time. You simply cannot bring anything of value to the Big 12, but you expect a power conference to give you a free handout so you could have "potential for growth"? Nothing would be more laughable, given your 2015 record:
2015 UCF Knights Football Schedule | Central Florida
You are right in that no one knows where UCF sits in the eyes of the Big 12, but I certainly hope it is not going to be based solely on "potential for growth".