Alright, time to step in here:
Sucker Punch won't be of much help regardless of STAB, as I'm planning on EV training speed and the Quick Feet ability will also be in effect.
Correct really, this move is pointless on Mightyena with Quick Feet and Speed EVs, especially when Crunch is available.
However, if this were doubles (in which case Protect would be mandatory) then I'd drop Quick Feet entirely and run an Intimidate set (with Sucker Punch STAB obviously,) which would be vastly superior in such an environment. For singles though, keep Quick Feet and Crunch.
Super Fang is a powerful move, but the 10% chance of missing worries me, especially if I'm against a Fighting Type.
Draco Meteor is considered one of the best moves in the entire game due to its massive STAB power combined with Dragon-type only being resisted by Steel. It also has a 10% chance of missing. 20% or more miss chance, fair enough, but 10? Give me a break, there's caution and then there's paranoia; this is the latter.
Also, since Super Fang always inflicts 50% of the enemy's current HP as damage, they'll always survive it and if they're a Fighting-type, they'll then kill Mightyena anyway. You're dead regardless of whether you hit them or not with it.
Protect is not a move I would normally use, as my usual tactic is to do as much damage to my opponent as possible, battle and otherwise, as well as conserving PP. As such, I would prefer to save that for another Pokemon.
Protect is there so that Mightyena doesn't get murdered before Toxic Orb has a chance to poison him (it takes a turn to activate, so you Protect on that first turn to keep yourself safe from damage.) Mightyena's speed is awful without Quick Feet active, and without Protect he's all too easy to destroy before the ability has a chance to activate. There's no getting rid of it here, besides, you're only going to use it once so what's the problem?
Also, "doing as much damage as possible" does not mean "I will only use attacking moves and nothing else." The former means using mostly offensive Pokemon to break down defensive Pokemon and then setting up with moves like Dragon Dance to mop up everyone else. The latter means getting your face kicked in by anyone with half a brain in their head because you have effectively no strategy whatsoever.
P.S. I should mention that for the third moveslot, Sucker Punch and Super Fang are both trash. Fire Fang is probably the best choice since it's Mightyena's best option for enemy Steel-types.
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