At this rate I would rather they give Shen a 10 min cooldown ult
than they can just buff his entire kit to be more of a juggernaut that lean more toward tank.
His play style is already quite similar to them so why not balance him as the same type of champion

"who needs an ult anyways"
Hell all four them function fine without their ult, their ult is only there to make it easier for them to do their thing. Unlike other juggernauts who ult are quite detrimental if they lose their ult.

Also I could now say my ult is on a Shen minute cooldown.
Although Maokai is getting changes in the Mid-Season tank rework I think Shen could be a good candidate to make solo lane warden work. With out being oppressive.