I can't really speak for Karma or Lux, but you leave poor Brand alone. What more do you want Riot to take away from him?
He can barely play mid at the best of times. He has no mobility, poor waveclear, and is arguably one of the easiest champions to gank in the entire game.
He has one of, if not the highest average death ratios in the game, around 7-8 deaths a game. If he's not super careful/doesn't have someone to help him out he will get caught out and die by the majority of midlaners and even a number of supports. I play brand mid/support and most of the time if I'm not ahead I'm stuck constantly trying to poke with w from my side of the lane because if I get peeled or cc'd I'm pretty much dead or forced to pop flash to survive.
Or the enemy jungler shows up and gets a fairly free gank. Early on Brand basically has the power of a wet noodle if he's ganked in the middle of his casting against the enemy in his lane.
He can't spam spells in lane because he'll quickly drain his mana pool if he does. You can't generally rush tear because you need to rush damage to have any sort of impact from your lacking kit.
His only cc requires him to land another ability first - a w with a cast time that's generally quite easy to dodge, or an e that requires him to step up to hit you. Plus, he, y'know, actually still has to hit you with the q. You can dodge it. There's actual counterplay. I know in this day and age that's a rarity, but it's actually there.
Once the game gets past laning phase his only real benefit is in teamfights, if the enemy is dumb enough to group up to get hit by his passive multiple times. He doesn't really have the damage to burst anybody down like the majority of mages do, and he's usually stuck constantly trying to poke to get any sort of momentum going.
I'm not saying that he can't be oppressive at times, because he certainly can, especially with an aggressive ADC like Draven - but the key to winning is actually pretty simple - play more passive and don't do anything stupid. If you do, they'll either overextend (that's generally me going for the e -> q) or push the lane far enough for any jungler with half a brain to gank Brand for an easy 300g.
It really sounds like you're trying to match his aggression, which is exactly what Brand wants you to do so he can hit you in the face with his spells behind his minions while not having to overextend. Just play back and you'll have a much easier time against him - I guarantee it.
Or, y'know, buy some MR to survive instead of just rushing straight for your first crit item.