His ult is fine, been playing him for years now. It makes him a MONSTER in duels thanks to the free and massive amounts of free Armor and MR. In Teamfights, you're usually ulting a carry, and since Urgot is beefy he can often manage himself well so long as he doesn't get overtly CC'd (which is an acceptable trade off for killing an important carry.
Besides, in practice that rarely happens, in recent memory I can't recall a single time I've ulted into 4 people for 1 carry. Usually it's fish for an E, then once the front line is weathered down you look to grab the ADC or Assassin, whichever is more important. From there you can comfortably 1v2 while your team cleans up.
Plus the recent change to fear nearby enemies after the swap makes those dives rather effective, it gives Urgot an opportunity to decide whether to E > QQQ or flash out.
... Also you're suggesting we give a champion a ~1000 range point and click suppression + blitz hook that also debuffs their armor/Mr.. Just let that sink in.