The New Sejuani Changes is Crap.

almost everything you said was opposite of the truth. the changes were a buff and sejuani is less incentivized to build ap for damage.

Ruined Garen? What?

First off more people have been playing Sejuani (who is an AP tank by the way) with more AP than tank as of late. Secondly you act like Sejuani will never be viable again. If their changes didn't hit the mark there will be more changes, calm down.

Also Garen very strong right now. I suggest learning how each champion is doing currently before saying they have been ruined.

Sivir got several buffs over the course of season 4. GP's fine. Garen doesn't know the meaning of the word "nerf." In fact he recently got a semi buff. Sej being finicky does not mean ruined. Jax still goes hyper carry. In fact he just got a buff. Shen needs some work to be able to hold his lane top, but in teamfights he still does his job. Singed only looks ruined because of how popular high mobility champions have become. I actually prefer the new Sion to the old one, who had probably the wonkiest build options in the game outside of Eve. Urgot? Not so much ruined as just left behind. I don't see Trundles very often, but when I do they're almost always excellent. "QQ he doesn't have a silence, even though he's still dealing the same amount of instagibbing damage from the slow" Shaco still stomps mid game. Nasus still stomps late game.

Anything else?

I think those change was good for her (except E)

W buff makes her clear faster because higher dmg and got lower CD, so she spam more skill if you max W over Q. % max HP was removed from Q, her Q is skill shot and it was her best damage skill, if you missed Q, you will get more punishment than now since her W cant be missed. E is trash skill now, jumping skill gives enough time for her E over after they land.