First, drop HOH's M. It's not accurate at all. < 15BB? Playing against a stack of < 55BB, what is the calling range of that bigstack? Wider than your pushing range?
Against a stack of 10BB, is that player's calling range wider than your pushing range?
You raised 2.5bb with A7? This is why you're not making it deeper. Then you push a weak Ace on an Ace flop. Let's see, if I have AJ+ I am calling... with any stack.
You have 15BBs, you're pushing 77+, AK, AQ, AJs from the time you have 20BBs especially when 55,000 chips is 15bbs and there is 350 players left. If you want to make the Final Table... the only place you want in an MTT.. is to get those chips in there.. and NOT with A7.