What if Tryndamere didn't do double damage on a critical strike?
Here is what I'm thinking: Tryndamere's critical strikes penetrate 100% of his target's bonus armor, but does 40% reduced damage. In other words, rather than 2AD on a critical strike, Tryndamere does 1.2AD on a critical strike that ignores bonus armor. If he gets an IE, the bonus damage provided by IE would also be reduced by 40%.
Here are what the numbers look like for 500, 750 and 1000 point critical strikes against a target with various amounts of bonus armor and 80 innate armor.
http://i.imgur.com/kVxVivk.jpg
Graphically, with no last whisper: black is current and magenta is proposed damage curve as a function of enemy bonus armor.
http://i.imgur.com/zFyCzfq.jpg
Graphically with a last whisper: black is current and magenta is proposed damage curve as a function of enemy bonus armor.
http://i.imgur.com/QhEdh5k.jpg
In summary this change would greatly diminish Tryndamere's ability to cheese lanes at level 2 or 3, and it would immensely reduce his damage to targets that have very low or no bonus armor, like carries. In fact, he does only 60% of the damage he currently does to squishies with this change.
As a trade off for doing far less damage overall, his damage becomes target agnostic-- it can't be reduced by bonus armor, only innate armor and large amounts of health or damage reducers like attack speed slows can mitigate his damage output directly, though his damage output already reduces itself by 40% for you.
Basically this change makes it so that Tryndamere doesn't really care who he hits, as long as he hits something. He does the same damage number to anyone, so instead of focusing on cheesing squishy carries in team fights as an assassin might, he focuses on just auto attacking as many times as possible regardless of the target as a proper fighter would.