I wouldn't put Gangplank or Fiora anywhere near Sion or Galio on this. GP and Fiora are still visibly the same people, and have kits that at least on a surface level do pretty similar things to their old selves.
I also think that, while Galio and Sion are both changed on a similar scale, I think that Galio had a lot more worth keeping than Sion, and I'm disappointed that a lot of it wasn't kept. Yes, I am not a Galio player, because his kit is shit and isn't worth keeping. But there's an appeal to his visuals, that Gargoyle look, that's completely lost with the update. There's an appeal to his story and personality, the sadness of it in particular, that is completely shattered when you press play on the teaser video and Galio yells "FEELS GOOD TO STRETCH MY WINGS!". With Sion, everything about him was dumb and it meant nothing that it left. I'm sure even if they don't like his new kit, Old Sion players at least like his visuals and story. I don't think Galio players will quite like their sad Gargoyle being turned into a joyful superhero man.