As a devoted Trundle player, I can say the pillar idea would ruin the utility of Trundle's best tools in ganks and fights. The slow is what makes the wall so significant, as people who have to walk around it have to take even longer to do so. Removing this slow in ganks and in the jungle where he can completely block a path would make his E just a long ranged blink, which doesn't serve Trundle's play style as well as a terrain former that zones and cuts off enemies. His current Pillar is very strong, for those who have taken the time to develop skill with it, and I don't believe it should be touched at all.
Contaminate: Enemy champions receive penalties equal to the bonuses Trundle receives. The penalties are spread out based upon the number of enemy champions. 2 enemies would receive 1/2 and 4 would each get 1/4 the value of Trundles bonuses
. From what I understand, you're just blatantly buffing his W by adding an extra effect right? I suppose this would be cool, but it might become imbalanced if you use his Q and R debuffs on one target. It in theory would just decimate
an opponent's stats beyond belief, lol. As for your R idea, it seems nice, and I do agree that the Ap ratio tends to be pretty pointless, but I'm not sure about your health percentage idea. Trundle players will use this at the beginning
of a team fight to enable a target to be a squishier focus, so this really doesn't play into Trundle's role into a teamfight, were he is often already full health when he uses it, and being a very tanky, but un-ignorable bruiser, who debuffs the carries and tanks, and provides his team with zoning, and massive debuffs. All in all I like your ambition, but if there is anything I would ever say riot should change about Trundle, it's the clunkiness of bite. There are many situations where the downtime of moving after bite is what made the difference when chasing. I believe Trundle is in a very good and balanced place, and just takes skill and practice to play well. His is my favorite Jungler, and one of my favorite champions in the game. Hope my comment gave some insight, since no one else seems to want to input.:P Also, if you're a fellow Trundle player, I salute you :3. If you're one who doesnt play him, take a look at stonewall and other players like me who use him very effectively and love him for what he is, and most of us will tell you he is one of the most balanced champions in the game. Never when I have gone 8/1/5, gotten an early aegis, and been branded as "op", and just good with him.