The biggest reason I think (I THINK) riot wanted to rework him is because he was overbearing and he had a toxic kit because "I hit my acid, you be screwed bro" or "I missed my acid, hey now buddy, we can be friends right?".
Essentially, lack of counterplay. But some thoughts.
You know what has always jammed my acid hunters? A Nasus, who rushes frozen heart, then begins to out sustain me, as I watch my mana supply dwindle and his health remain the same. Chogath, Mundo (smart ones anyway), Malphite, ect.
Essentially, any tank, who builds tanky, with sustain (not necessary but a plus), will counter Urgot in lane. By the time I can get a last whisper, I have to shell in for some essentials: boots, tear, brutilizer, I can't rush that like they can rush armor.
But wait, the tank meta is back and they are strong now? What?!?!
Also, just to say this, Nocturne can be tough cookie too. His spell shield and fear is is able to disrupt the eqqq, and his stickiness can be a problem as well.
Now, if you want to rework Urgot's kit because you think there are cool things you can do with him, that there is a role which you want him to fill (for your quest of making every champion unique), or if there is some greater higher thingy that you have planned, by all means rework his kit, but not for sake that he lacks counter play.
I mean. let's not forget that he already tends to shove lanes, be susceptible to ganks, and has low mobility .
I am silver, so what do I know?
TLDR: Is Urgot still going to have a kit reowrk?