1
OPÂ
Pick or ban exept fizz and sylas because they are very skill reliant
2
Very strong
beleive in them they will still have utility even if they feed not like that garen we met in soloqueue
3
Fairly strong
they are better picks at the moment but if you like them feel free to play them they are very strong but a lot of dumb players them (wich is not your case buddy)
So, let's see, for Tier 1, I agree with most of your picks, however, I must say that Xerath is very skill reliant, since all of his kit revolves around skillshots, and Kassadin, well, it depends on whether you know how to farm and survive laning phase consistently. While other picks such as Sylas and Yasuo are rather niche since they can be countered by certain team comps.
For Tier 2, I would move Swain, Corki, Karma, and Pyke down to Tier 3 because they are very situational champions that can be easily shut down by those in Tier 1 and even Tier 2, By mobile assasins like LeBlanc, Zed, Kata, etc. Oh, and you should probably add Pantheon in there too.
And finally Tier 3, this is one is pretty accurate. Some picks that are not traditional at all, like Kled and Kindred, I would consider taking them out of the list, but setting them aside. It's a pretty solid tier list, especially because you included most skill intensive and scaling champions, such as Qiyana, Irelia, Akali, Vel' Koz, and Lucian there.
That's it, I hope this review came out as positive and helps you out in building any future tier lists. Do keep in mind this is from my own experience and an opinion only, so feel free to correct me or defend your reasoning behind your placements. :D