I need help with my play. Thorough explanation inside.

Hey guys, I haven't played league in a while and just recently came back and started getting into it. I was hoping to get some help with my gameplay. I've included a link to my op.gg, feel free to poke around in my stats in any way, using any site.

I feel as though I have determined what my problem is, however knowing how to fix it is something that has my a bit more perplexed. I have some really great games, where I carry hard, even if my team is doing terribly, and other games where I feed hard, even if the rest of my team is doing well. Overall, I feel I lack consistency with my play, and I don't believe it's anyone's fault other than my own. I don't feel when I do poorly that I'm getting outplayed by my opponents, but I myself am just making dumb mistakes.

I also have been having a bit of an issue trying to determine what role is best for me. I am a very strategic player. I don't do well when I do do well because of my micro, but rather because I know how to control the map well, and am able to predict enemy movements well. That leads me to believe that I'd be a better jungler, or mid laner. But my champion pools in these two roles are extremely limited. Currently, my only truly 'good' jungler is Kha'zix. And for Mid Lane I'm pretty much stuck with Annie and Kat.

I enjoy playing ADC, but it takes my weakness as a player, and magnifies it by a hundred. My consistency is absolutely horrible in the role, as you can probably tell from the match history. One game I'll go 32/6/7 as ADC, the next I'll go 5/8/0, 3/7/0.

So I ask, how do I fix my problem with consistency? And is my champion pool severely limiting my abilities? Perhaps the two are somewhat building a problem off one another?

The only thing I ask is you don't tell me to play more games, as I am a long time veteran of the game and have plenty of games under my belt, I want to start hammering out specific kinks in my play. If you require more information, please let me know!