I don't fail all the time dodging the hooks, my team does. Because of that I find blitz to be op, even if directly he doesn't cause my death and loss, indirectly he does because his hook is difficult to dodge if the blitz is half decent. He does this by feeding his team to the point that they out damage me or negate my damage by tankiness. I don't have to be grabbed for him to be op. There just has to be one or two guys on my team who don't know how to dodge blitz q's for blitz to be op. I just avoid blitz to avoid being grabbed, stay behind minions, and try to go in when it's on cd, even though the cd is relatively low. Hell, the nerf could be a meaningful cd at max rank.
I main Lee. I don't find him overloaded. Play him a bit jungle. Tell me about all the damage the e does. The slow is helpful, but, so is a knockup that deals Double your ad. A shield is helpful. If only blitz had one, like in his, i dunno, passive? Blitz ult is also on a 23 second cooldown, and the passive damage from it isn't really negligible. It can do a lot of damage. cooldowns are actually relatively close at max rank. Lee's are a little lower, but blitz offers much more hard cc. His primary displacement tool(q) is on a much shorter cooldown than lee(r). Probably the only think overloaded about lee is his mobility, his ability to run away and to chase, and therefore kite and outplay, is huge. But to do that right you have to be good. He doesn't out damage most champs in a fight without having a prior advantage. Lee gets built ad assassin. He also gets built ad bruiser and tank. In all those iterations, his q is the most of his damage besides his ult. On tank and bruiser, it's almost all his damage. Bruiser does give a little more damage on e, but it's not that huge, it's good for the slow. It's good for the cc. Blitz's e is better cc, it's a knockup. It does double your ad. Which means it's going to out damage Lee e if they both build ad bruiser, which is viable on blitz. So, it's single target. thats the balance for it. The blitz w is weaker than the lee w, but other parts of blitz kit make up for it. I really don't see how lee is overloaded compared to blitz.
Also, i think that by nerfing his q you could buff the rest of his kit. make e maybe have a ratio in addition to what it already does, and remove the slow from w maybe, or increase the aa steroid on it. Tweak the ult, though i think it could remain the same if the q was nerfed and the other two skills are buffed. This would accomplish op's goal as well.
Basically, i don't think he's a one trick pony who's damage and effectiveness revolves around his q. Maybe with certain squishier support builds it's a problem, but not usually. That said, i do think they should nerf his q and buff some of his other skills, as it would make him a better rounded champ, and make his non support builds more viable, while taking some of the power from support blitz, for whom the q is a bit too strong.