There is no melee or crit bonus. Heavy afk bots do half the damage, and take 33% more damage.
I tested them myself before I released them which is why I know they are bad.
They just run straight through sentries or hotspots and get instantly killed without accomplishing anything.
I will try increasing the damage they receive a little.
Personally, I don't have an issue killing bots, however it ruins the pacing of the game.
So I'm up against two scouts and a heavy, fair enough - I'll focus the scouts first as they're easy.
One rocket, two rockets - one scout down. One rocket, two rockets - oh, he's still alive - oh it's an AFK bot.
I've had situations in which I've thought about spectating a pyro because he seemed to be using an airblasting hack.
Every single rocket comes back at me, I get suspicious and go into spectate - oh, it's a bot.
It's the best player that I've seen at airblasting - and it's a bot.
Playing engineer is very strange with AFK bots on the other team, as even scouts can distract the sentry for a lot longer than they should.
I've seen players who let the AFK bot go around the corner first, knowing that it will tank the damage of the sentry whilst they destroy it.
I don't see any reason why the AFK bots should be harder to kill than the default TF2 bots - people don't complain about bots being too easy.
It becomes an issue when people see bots as having an advantage over them from the damage reduction.
I don't understand why the bots need any enhancements at all, really.