As far as I'm concerned, critical strikes are a problem in League because of a pair of root issues.
It stacks in an additive manner.
It only really benefits one type of offensive stats.
There are two ways that I like that crit chance is/was implemented in other games. Those are DotA 2, and Dawngate.
In DotA 2:
There are a number of items and character abilities/talents that provide critical strike chance.
Each source of it has their own chance to proc, as well as its own damage multiplier.
e.g.
- The Crystalis (item) gives a 20% chance for 175% damage.
- The Daedalus (item, builds from Crystalis) gives a 30% chance for 235% damage.
- Phantom Assassin's ultimate provides a 15% chance (or 20% with a talent) to do 230% / 340% / 450% damage.
These are exclusive from one another. If multiple sources of critical strike proc on one attack, then the highest multiplier is used, discounting the rest.
So while you get a higher chance to crit with multiple crit items/passives, not only are you not getting the full value of the already-expensive items, but you're also losing out on other powerful item effects by filling your inventory with just crit items.
This means that individual sources of crit damage can be tweaked as needs be. If a hero's innate crit was too strong comparatively? Hit it and you won't affect others. Too weak? Buff theirs. You can't do that in League, as the only effective critical strike sources are items, Pantheon, Shaco, and Tryndamere. They all pretty much share the 200% damage multiplier across the board, too, instead of having different ratios. (Aside from Jhin, Shaco, Yasuo, and Kalista/Jinx, by virtue of their altered AD -> AA damage ratios.)
In Dawngate:
You couldn't buy critical strike as a stat in and of itself. Instead what you bought was a stat called Mastery. Which did two things per 1 point of Mastery:
- It gave you 1% additional critical strike chance on your autoattacks, additively.
- It gave you 0.5% additional ability damage, additively.
That's all well and good, it immediately is more attractive to all sorts of characters instead of just rightclickers.
But your character class in Dawngate determined what stats you got from the basic stats Power and Haste.
- Rightclickers had high Power -> AA damage scaling, but usually low Power -> Ability numbers scaling. They had high Haste -> Attack Speed scaling but low Haste -> Cooldown Reduction scaling.
- Casters (mainly mages) had low Power -> AA damage scaling, but usually high Power -> Ability numbers scaling. They had low Haste -> Attack Speed scaling but high Haste -> Cooldown Reduction scaling.
- Bruisers and Assassins lay somewhere in between on those scales as they were meant to rely on both AA and abilities relatively equally.
Dawngate's derived stat system was amazing and I loved it to bits (hell I loved the game to bits), but that's beside the point. It meant that you couldn't build entirely dead stats on people (like AP Riven, or crit on a full AP mage).
It's probably not practical to try to do either of them at this point in League's lifecycle though (Dawngate's style moreso). It's too mature around its existing system, and perhaps a little too brittle to try to change it up that drastically, without breaking things.