Let's talk about Evelynn

I used to main Evelynn, since she was "trash tier" before her rework, and through season 3 when she went through being unplayed, then considered OP, and then nerfed back into line so she needed skill both to play and to play against (she was considered balanced or slightly weak at the end of S3).

Then came season 4 with its vision changes. Suddenly, she gained a huge amount of annoying power because you couldn't use pink wards against her any more. It was fun to play her like that, but no longer fun to play against her because she had very little counterplay - either be strong enough to blow her up if she attacks you, or hide under your tower.

Instead of dealing with the bigger and harder-to-solve problem - that her stealth had become unfun again because of the new vision system - she was "fixed" by giving her nerfs and changes to shift her more towards a sustained autoattacker role, and to try to make her "bad enough" as an assassin to compensate for the broken stealth.

I loved playing Eve because she was a squishy, stealthy assassin, who had to carefully stalk her prey and pick them off at an opportune time, could only kill people alone if she got the drop on them or was really fed, and could be blown up instantly if she made a wrong move. A true AP assassin.

Now, I don't really want to play her at all any more. You can still build her as an assassin, but it's just so suboptimal compared to her tank build. Forget about strong or weak, the very fantasy of the champion is ruined with that build. You have to build her like a tank instead of an assassin. That's just not fun for me any more. That's not what Evelynn is supposed to be.

I think the only way that Evelvnn can be fixed is to completely change her interaction with wards. Make it so that normal wards can see her, but only if they are inside her stealth range, so they see her at slightly reduced range. She would also still be invisible to minions and to champions outside of her stealth radius. (I'd also consider making her invisible to towers outside of her stealth radius, since they can currently see her much farther away.)

Her damage would need to be buffed to compensate, as this would take away her biggest strength, but it would fix her frustrating invisibility while still allowing her to use her stealth to outsmart enemies. Her skills could be given power again, allowing her to actually be the AP assassin that she once was.