The Herald Isn't Broken
Just had a match and I can actually see how it is not as broken as every thinks it is. The big chunk of damage it does to towers is only in that first charge it does, and beyond that it will just stand there doing normal level auto attacks to it. While it is tanky, it's just gonna keep taking tower shots so if it's after your tower it won't pay attention to you while you hit it's weak point meaning the team that summoned it have to protect it to get the crazy push. And on top of this you can actually FAIL to summon the Herald if you have it. If you move (or probably even get hard cc'ed/knockedback or something) and the channel is interrupted you lose the item that summons it so no big bad beetle for you. So here is how to deal with the Herald, send 2 people to that lane. If it's in the top lane and only the Top laner that summoned it is there, then the opposing top laner and their jungler should head up there and either kill that laner or chase them off so they can make quick work of the Herald. If it's a seigemaster strat with something like ZZ'Yorick then you might need the midlaner to assist in this.
So in short remember, if you see a mutated scuttle crab charging through your lane, do not panic. Instead call on a teammate and pair up to get some crab meat.