Worst wave clear for a mage in the game, mediocre range, no zone control, no real poke, almost entirely skill shots, half his core combo is delayed damage.
What's 2% on his passive going to do? Besides maybe make his supporting not as shit (before some ADC starts shedding those tears it was at a 45% winrate, now it's 47%, waw).
I use to be of the opinion that the lack of wave clear could be used as a balancing tool but ever since you gave Leblanc of all people incredible wave clear I really don't see a point of even pretending like the subtlety here exists. Give Brand real wave clear, so you can play him mid. Stop beating around the bush. He doesn't need more damage (even though he really does), he doesn't need a trickle of mana back with his E (everyone rushes RoA or Morellos, seriously this isn't season 1 where you build 3 dorans then rush rylais), he needs wave clear and everything that entails so that at the bare minimum he has the same basic options every other mid lane mage has in the game.