Tahm is interesting
the way his E works makes him a lot better at being a strong answer to poke and harass combos, and a lot worse at sitting in the middle of a team fight or winning long trades.
It's a pretty interesting niche that hasn't been filled yet, being a tank who can absorb poke and poke back, and while I still wouldn't consider him anything near a good design, this is a respectable step forward.
I think the main issue with this is the timing; game is all about deathballing now, and the poke comp where he would be ideal into hasn't been a thing since season 4. If he ends up truly being weak after people adjust to this/after he appears in pro play, I would prefer enhancing on this niche somehow rather than buffing generic things like damage or basic durability
I'm interested though, Riot, good job