Strongly disagree with all your S tiers nerf list
Miko probably the closest to being op and is mostly good because it has the best sustained heal with the smallest effort, just beam in the tank butt and profit. In case something goes wrong stun spore +hide +heal but he relies on escape if he get focus so is really squishy
Alani got nerfed hard and its epic in clutch heals and hold the lane, thats it. her dmg is nowhere near as good as release and she breaks easily with some pressure
Thorn is really good nuking people out but you need to be in perpetual move to be a threat, if you stop moving for a sec you can die fairly easy. And she has a small hit box with a not so small head.
Boldur is a nice tank for sure, but nowhere close to s tier. Endgame hero with slow attack and team attacking depending.
Personally in the last case since it is my favorite role I can tell you that if boldur is S tier in your book and deserves a nerf, kelvin is SS in mine and should be erased for the game.
With the same boldur time to build up you can end up with more raw dmg, more secure cc, 3500- 4000(lazy) hp pool + shield sustain with low cd and eldrid regen as boldur and with shield caps gear you can sum more shield . If you have a good healer, you are in god mode bitting for 700 dmg (thorn ult) and punching people to dead.
we shouldnāt be asking for anymore nerfs.