3rd, Tryndamere R rework
Currently, Tryndamere is at a very weak scaling states, he can dominate early and then somewhat having pressure on the map, but what he accomplish with a gold and level lead is a lot less than most other late game scaling champion (Irelia, Riven, Jax, Fiora, etc ...) and not only compared against top-laner, a lot of other champion in other lane scale better than he does nowadays with a gold lead.
Here what could be done to improve his R fantasy, as well as increasing his weakness early game and strength late game :
Base stat :
AD : 69 -> 65
Health 626 -> 580
Attack range 125 -> 175
R changes : (Undying Rage)
Cooldown 110/100/90 -> 140/110/80 seconds
On activation, Tryndamere gain 20/35/50% movespeed toward enemy champion and 40/60/80% attack speed for 10 sec
If tryndamere would be reduced below 30/50/70 health during this duration he enters undying rage for 5 sec.
Whilst in Undying Rage, Tryndamere becomes immune to damage and can't gain or lose health and keep his move speed and attack speed boost for the duration of Undying Rage.
At the end of Undying Rage (5 seconds duration) Tryndamere dies if he didn't had a takedown during his ultimate duration (before and after Undying rage activation)
If he achieved a takedown during his Ultimate duration, Tryndamere is heal for 30/40/50% of damage he dealt to enemy champion during his ultimate.
This ultimate would improve his teamfight fantasy, and remove cases of ultimate usage just to split push. This would also improve his design by nature, if he get overpowered afterward, further base stat nerf and/or higher early game cooldown on W (Mocking Shout) and E (Spinning Slash)
Dearly, A Tryndamere lover