I wouldn't say that the Bandit in general is OP even though I'd say that Bandits got the micro advantage against Glaives and Scorchers. What I mean by micro advantage is that Bandits will win for cost when they are using fight commands against incoming Glaives and Scorchers. If the Glaive or Scorcher player want to destroy the Bandits he needs to find a way to close the distance or catch the Bandits off guard.
However Bandits are one of the slowest raiders where only Duck and Archers are slower so Glaives and Scorchers can outmaneuver them and attack them from several angles to be able to close the distance.
But because of the low speed Bandits have trouble catching Pyros or surrounding Venoms.
When I go hovers or spiders I don't fear Bandits. I fear Glaives.
Glaives speed and cheap cost makes them the best raiders to counter flea harass and you just need 2 Glaives to beat a venom. Basically Glaives can shutdown spider expansion and prevent flea harassment in 1v1.
Glaives regeneration of health and speed makes it very hard to kill them with Scrubbers, hover raiders.
Bandits are more expensive than Glaives and can't really run down a Venom or regenerate health after being hit by a Scrubber.