"I got pulled thru an entire building (4 walls) the other day."

this seems to be your sole reason to make this post. Truth be told, his hook is bugged in a lot of occasions, but it normally works as intended.

On your point that he has self heal and the possibility to one shot, that shit comes with a hell lot of downsides. Miss the hook and you are defenseless, since your range and mobility is the last piece of garbage. "Oh but he can heal if he is in a shitty Situation", yeah good luck getting cheesed on while you have to stand still to heal. D.Va and Winston can easily jump out of a shitty situation, roadhog gets buttfucked. As for zarya, her capability to save teammates and deal a fuckton of dmg with her charged beam easily outclass roadhog in most situation. And dont even bring Reinhardt into this, his synergy with a good Team is beyond that of every other Tank.

Ultimately, Roadhog is totally ok the way he is. An enemy team can save a Teammate getting hooked with a Zarya shield, which is mostly the case in higher elo. His Pick potential and Damagesoaking body are his identity in this game and should remain the way they are (otherwise he would be outclassed way more by other tanks than it is already the case in my opinion).