So simple oxidation blocker like aluminium would still make it useless?
By the way there are even stronger acids like hydroflouric Acid. A mixture if Nitric acid and sulfric acid is way more potent, the dangerous about flouric acid is that it ignores clothes and stuff and that it even ignores the skin, it is direcly attacking the bone and reacting with the magnesium in it and so slowly but steadily eroding the bone.
In theory pure hydrogen-ions would be the best acid possible but here well, they would react with eachother.

Mhh so why not having an organic salt in your blood which normally binds the oxygen for transportation. It would then leave positive loaded hydrogen which is then bonded by nitrogen! In contact with the air the normally pressured hydrogenacid would get first into a gasious state before turning liquid and eating it's way through flesh since it's highly potent. The same could work with hypochlorid acid such attacks the skin also more painfully. It would give you some range and also could more likely act as a protection for your body so that your own acid does not aatack your own outer skin which is less resistent against it. If you want to can search the name of the acid which can even corrode gold but I think 100% hypochlorid is more nasty, at 36'5% it hurts and well that's the highest concentration you get when it's liquid...100%? Gosh I am a chemist but don't ask me!