more of a mocheeze issue than a medic issue
Therefore Mocheeze needs change. If you have two people as medics, there is really no way to lose, now keep in mind a medic chain can be broken, but it is near impossible.
Mocheeze, if his snowball had reduced direct damage, and some extra knockback, it might make him a little better.
This might work, but if the damage is unchanged, then someone who knows the basics of Mocheeze(hold shift+spacebar then spam missiles, no other attacks) cannot die, there would be no class to use to fight him, everyone would revert to Overweights hoping that the damage would kill him off.