My ideal buffs to my tanks.
I play a lot of sion and a significant amount of poppy, and with the tank update nerfing tank items (and therefore tanks) actoss the board I've come up with a few ideas on how to buff them.
Sion: A) increase health gain from minions to 3, and champions + large monsters to 15. This is to encourage toplane and jungle sion who last hits a ton of minions and kills a ton of monsters instead of support sion who does little of either.
B) increase the base damage of his uncharged q. From 20-100 + 60% as to 30- 150 + 70% ad. This encourages sion to trade a lot more with q even if he can't get the stun.
C) increase his w health scaling from 6-10% to 8-10%, maybe even 8-12% with rank. This allows sion to trade better in lane and take more punishment in the earlygame from all the increased mixed damage sources.
D) increase base damage of e at early ranks form 70-210 to 90-215. Simply allows better trades in lane.
E) have his passive give him move speed towards champions scaling with level. As it stands his passive is best early when people can't outrun him Andrew 50% ms boost, but the later the game goes the less valuable the boost becomes ( his life steal too, but that's different) so let him catch up to all those fast champions at higher levels.
Poppy: A) increase q % damage to 8%. Straight damage buff to champions.
B) increase base mana. Straight buff to waveclear.
C) increase passive shield duration to 4 seconds. More shield makes for better trades.
D) change e damage to 50-100 + 40% ad from 50-150 + 50% ad and have it deal double damage on wall collision. Good poppies now have better trades in lane.
(Poppy has fewer and less complex ideas because she simply just needs buffs and is only viable toplane anyway.)
And that's about it. Personally I most prefer A) and C) for sion, and C) and D) for poppy.