Well, there *is* a special formula, but they tend to keep it to themselves. 
Don't worry...you're where I'm hoping to be back to 12-18 months from now, and when I was there before I would not have felt the least bit of trepidation about the apps you intend to make. The only thing I see possibly holding you back at all is they may constrain your credit limits a bit based on your income. But with your util super-low (I'm guessing from the fact you always PIF), you are positioned as well as you possibly can be. Your income is what it is, but your debt to income ratio and available credit looks great.
Starting: EQ 626 (myFICO 7/22/12), EX 696 (TU FAKO 8/14/12), TU 621 (CK TransRisk 7/24/12) Current: EQ 665 (myFICO 2/13/12), EX 690 (CreditSesame FAKO 1/6/13) , TU 681 (WalMart 2/4/13) Goal: 700+ x3
My Wallet: Amex Zync NPSL (hidden limit > 10k), Barclaycard Apple V $2000, Walmart (Store) $900, BoA Cash Rewards V $500, CreditOne Platinum V $600, Best Buy Rewards MC $500, Chase Freedom V $400
Dream Wallet: Amex BCP, Citi Dividend Platinum V , Chase Freedom MC, Chase Sapphire Preferred V, BoA Privileges Cash Rewards VS, UPromise MC, US Bank Cash+ VS, Amex ZYNC, Amex SPG, Amex Platinum, Andrews FCU Global V
