What niche is he filling exactly? He's literally just a wall of meat that statchecks everyone and has a singular instance of interactive gameplay through his Q, which ironically makes him extremely uninteractive in lane since he just last hits with cleavers if he can't successfully statcheck yet.
There's something that every Juggernaut in the game has: a gimmick--something that has to be played around and has high impact to compensate for reliability; be it tentacles, spires, ghouls, Darius Q & stacks, shotgun knees, etc.. Even Garen has a more fleshed out design in terms of interactivity and niche.
I know people like to meme about Skarner being the worst designed Juggernaut but I'd say it's Mundo by a mile.
PS Edit: I'm saying he's too one-dimensional and statcheck reliant at all stages of the game. Not to mention extremely dull to play against in lane.
> Dr Mundo needs a bit more overall durability if he is to successfully go where he pleases.
> R - Sadism
> HEALING 40/50/60% maximum health ⇒ 50/75/100% maximum health
NO NO NO NO NO STOP! STOP RIGHT THERE! STOP IT!