Kassadin; lowest win rate in game? (Suggestions to make him a useful champion)

Kassadin; lowest win rate in game?

Kassadin seems weak right now, here are some changes i think could help, and also make him a more viable jungle. (I know he was nerfed cause he was very powerful, but he seems to be in a poor state right now.)

Increase base armor or attack speed maybe (attack speed is low), armor helps a melee champ, things that could be worked in per level would be helpful.

Passive- I don’t know if 15% reduced magic damage is that great, he can still be demolished very quickly. Perhaps adding in 15% magic penetration (the same way void staff gives 35%) would help the low damage output of Kassadin (especially sustained damage)

Q - This could deal some splash damage now at the same rate. Maybe The shield can grant bonus AP while it is active? Maybe grant 10% of AP as MR?

Also; Has 50% cool down and refunds 50% of mana cost if it kills a minion (Kassadin has no ability to lane against champs with harass. This along with the splash would help a lot)

W - The passive damage scales with points (rather than flat 20) ~ 20/25/30/35/40 damage per point invested.

This also increases armor by 10/20/30/40/50 +(5% of AP) for 2 seconds ; This because Kassadin will always lose trades with melee champs.

Auto attacks reduce the cool down on W by 0.5 seconds: This would be to help him jungle, as 90% of his sustained damage is auto attack, and his clear should be like other mages, (similar to nidalee)

E - This seems fine.

R - This could get some bonus from AP (10% and 5% per stack or something), but it doesn’t seem that bad. Maybe lower the internal cool down to 4 seconds. The range could be upgraded by 100 units or something, even spamming the teleport champs like Volibear can easily catch up to Kassadin. (Having this scale soley on mana gimps a lot of builds that could otherwise be great for Kassadin because without mana his Ultimate is not very strong)