I think to make the game more complicated since everyone from dota/hon wants that.
I'll suggest couple of things, since I am from Dota/HoN too.
Blitzcrank hook thing, can also hook allies so it could be used as a support skill and will actually need more skill to make it effective, in exchange pump it's cast range a bit.
Knockback skills like Tristana's ulti & Alistar's headbutt should work like Poppy's charge.
When the targeted unit collides with a terrain it'll deal more damage and stun for a bit, if the targeted unit collides with another unit it'll deal dmg to both of them.
Ashe's ultimate, make it smaller please. seriously its size is ridiculous and takes very little skill to hit. Decreasing it's size to a normal volley shot arrow add more glow for the effects, increase it's damage dealt + in exchange for the stun how about it actually freezes the target "like the one on the trailer", the target will receive additional damage from physical attacks but will be invulnerable to magics, lasts for 2/2.5/3 if not hit, breaks instantly if hit physically but amplifying the physical damage by 2x. The initial damage depends on the range before the target is hit. It also hits minions.
Vladimir's blood pool, it says he can't be targeted but doesn't say he's invulnerable, so AoE damages hitting him would be logical, and to lessen the people complaining about his blood pool.
And for my hero suggestion. 
Since we have asian characters mostly chinese warriors and ninja's how about a SAMURAAIIII!!!
About his story a rival and close friend of Master yi bla bla bla, he followed him to the league of legends to even the single battle he lost to yi a rock,paper,scissors battle. and with that he want's to show the might of his school/style whatever you want to call it.
His name Sensei Nakamura.
Combination of range and melee fighter. He uses long dual katana to look very bad ass with a traditional unamored samurai look and a bow on his back.
His passive. Arrow crafter generates 1 arrow every 5 seconds maximum of 12.
Q skill "Arrow barrage", he draws his bow and fires all arrows he has into the air to create a barrage of arrows from the sky. after 1 second arrows will begin to rain, in an order of 1 then after .2 seconds a couple then after .1 second all remaining arrows. Each arrows deal 13%/16%/19%/22%/25% of his physical damage. Work's like Rylai's Ulti where there is a chance you wont be hit or will be hit a couple of times. Has no cooldown, since it's damage and cooldown depends on your arrows. which generates 1 for 5 seconds. Cast range Regular range unit like Ashe and far range like Cho gath's rupture. Close range areas can not be targeted. Area target skill.
His W skill, Kamikazee "Divine Wind", Sensei Nakamura sweeps his sword so fast it creates a line of wind that pushes and damages his foes. Work's like Invokers deafening blast. Deals 50/65/75/85/100 true damage multiplied by your attackspeed. Pushes opponents depends on how close they are to you. Cooldown to be decided.
His E skill Pin shot. once again draws his bow and shoots at a target, dealing 60%/65/70/75/80% of your physical damage to an opponent. Pinning them to any obstacle behind them, pins both the target and the unit behind it if there is for .5 second. Cooldown of 5 seconds cannot be reduced. REQUIRES AN ARROW/ WILL REDUCE YOUR ARROW SUPPLY BY 1. cursor target like flash, and will hit minions.
His ultimate Honorable blow. Instantly kill the target if it is below 150hp/200hp/300hp if the target is not killed it will apply fatal wound. works like rupture of bloodseeker. deals 8% of your physical damage to an opponent as true damage per cell move. lasts for 3/3.5/4 seconds. Cooldown to be decided.
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