If I had to make TF3, I think I'd make Medic less essential and try to add more things for Medic to do. I really like how Paladins has healers where their healing is passive or burst, so they have time to actually fight without having to sacrifice healing time. I especially like Furia... She's rewarded for healing her team with Wrath, which both makes her fun to play and gives her selfish reasons to be a team player.
Also, I'd make Spy better in competitive, I think... He should be able to run a little faster than someone if he's close to them and they're moving and facing away from him.
I'd give Scout more movement options in general to reach higher places or out-maneuver enemies. That's kind of his thing
I think I'd want to give more classes a "my time to shine" thing like Uber/Conch/Banner/Backup... Soldier and Medic have them, but I can't really think of others.
I think for Heavy I'd change the Buffalo Steak Sandvich to be a charge-up rather than a cool-down, like Soldier's secondaries. Heavy doesn't get enough chances to punch people.
Engineer... Hmm. I think something along the lines of "over-charge your sentry to make it go bananas and then explode" might be cool? Also, he needs more buildings.
Spy should get something that requires a lot of stealthy set-up, but goes off all at once while he strikes some refined, casual pose.
I have no idea what I'd do for Demoman, Pyro, Scout, or Sniper for hero moment abilities.
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