they described juggernauts as immobile fighters, focused on being tanky, while their job is to deal damage.
the second group doesnt even fit for the most part. rammus and malphite are both tanks with strong initiates and disables. singed is kindof a special case.
voli definitely fits, olaf aswell, so does udyr. shyvana was just reworked, so its unlikely they give her sweeping changes so soon. mundo could fit into this.
but even if they fit the description, it doesnt means theyll actually get reworked. the item changes alone might make a difference enough for them.
and theyre currently working on voli and make changes to his ult. it will grant a bonus jolt of electricity against the nearest targets, when he activates it.
so id say 50%, maybe less since mundo isnt an ad bruiser.