As a Brand main, the nerf is completely justified.

The Swain nerf might be too much, and could be the Cinderhulk fiasco all over again (Cinderhulk is OP, Sejuani and Sion get nerfed, then Cinderhulk gets nerfed, Sion and Seju remain unfairly weakened) - but the Brand nerf is completely justified.

He's been one of the top % winrate mages even before Preseason, up there with Malzahar and Lux. And that was despite his growing popularity, so the "it's a niche champion so the mains boost the winrate" effect is only partially to blame. He's proven to be too strong in this meta, even on people who haven't mained him, even without items, in the support role.

Factors that have contributed to his OP state:

• Buffs to Liandry's and Rylai's - they give 180 AP now, used to be 130
• Buff to Rylai's slow
• Nerfs to Aegis of the Legion, the item that used to counter him the most
• Emergence of health-stacking toplaners and junglers with the new Juggernaut items (Sterak's Gage, Titanic Hydra)
• Nerfs to his greatest counter (Fizz) and decline in popularity of other mobile assassins (LeBlanc, Ahri, Zed)
• Buff to Doran's Ring (scaling regen), allowing him to ditch Morellonomison (he makes great use of % regen due to high base value of 8, higher than all midlane mages with 6)
• Same principle: buff to Frostfang (insane 150% regen) which he already had obscene synergy with
• More snowbally games, making use of his two-item (Rylai's + Liandry's) power spike before he falls off (his winrate drops below 50% in drawn-out games - as soon as people stack MR and/or kill him before he casts his shit, he's useless)

My only concern is that rash nerfs could kill his midlane presence and push him to the support role, which already happened to Zyra. I think most people will agree that Brand should be primarily a midlane champion. If anything, a good way to nerf him would be to cut his base damage and put some of that power into scalings.

I mean, we're yet to see him picked in the LCS, it has never happened in the 3 years of EU/NA history. And if the nerfs pile on, he might be dumpstered before he gets picked in season 6, even in the support role.