There's alot of tactics I've used that have cut CPA (and thus increased profit) SO much...
That are also so basic, just being aware and taking two seconds to apply them is enough to increase your ad scale and profit. The "matching" technique to find your best benefit and isolate the entire ad funnel JUST to this is one of them.
Few times a week I will be sharing these in micro 1 minute trainings. Let me know what you think & leave a like if you like :P