Skarner buffs are nice. Still have yet to see if he can get things done in major team fights with regular farm (non-super fed), which I do not see happening yet. Typically, Skarners in most games I play suffer from not being able to complete much of their build. They spend lots of time trying to outharass or gank people by dragging them from their turrets. If they don't have a good lane match up (he is not that great with most match ups in the first place), it is very likely that he will be underfed. That means jungling could be a better option, but again, he has to get some items to deal damage...meaning he will not be very tanky in team fights.
Graves. The naturally tankiest ranged AD carry with the highest AD burst, an escape/attack speed steroid, and good (although hard to use) utility with his smoke. He falls off after a certain point without good and steady farm (like all ranged AD). Could use a little tweaking on Q's total damage output. Escape does not need a change. Smoke bomb does not need a change. Ultimate is an ULTIMATE, and I do not think it needs to change much either (maybe a little scaling bonus AD nerf on the ult).
Remember that OP champions that get nerfed used to become unplayable (some still do, i.e. Morde). Powerful champions should only get slight tweaks.
For Akali QQ'rs...there are ways to deal with Akali. Gragas will beat her in lane (assuming Gragas can land skillshots). Lee Sin can reveal her. She's an easy target for your carry that is not getting focused by her (she can only really deal with one target at a time).
Thanks Rin! <333