Mechanical skill is important. It comes with playing the game over and over and over...and for a long period of time. But what i have found that helps to win in solo queue is playing early game champions that can snowball your team. Use the early game champions to control dragon and the map, as well as get other lanes kills. If you get ahead early, the vast majority of the time, it leads to a win...b\c unless youre in diamond or higher, people dont know how to properly come back from a bad early game. They end up going way too hard for kills and objectives that they dont have a shot at getting to make up for the not so great start. Which then in turn keeps your team ahead and snowballing the lead into a win. Also....purchase early wards and ward the area around your lane. Spending 75-150g is super worth it if it keeps you from dying to a gank. If youre a jungler, you should ALWAYS buy wards every time you recall. Place them in spots where your team can take advantage of the information. Info is everything in LoL. The more info you have, the more you can take advantage of. You should ALWAYS be working toward gaining an objective (towers, buffs, dragon, baron, inhibitors)....at all times! Dont get sucked into the constant teamfighting for no reason mentality of lower elo. They always want to play team deathmatch, and objectives are secondary to them. Teamfights shouldnt be happening unless the 2 teams are fighting over an objective....it doesnt always work out this way b\c sometimes fights happen, but you get the idea. As for your champions you listed...zac is the only "early game" champion b\c his ganks with his E are very strong. Kayle and Rammus tend to be more late game champions. Lee Sin, Xin Zhao, Evelynn, Renekton, Draven, Lucian, Corki, Leona, Nunu, Darius, Elise, Gragas, Jarvan......these are some strong early/mid game champions that can help you to snowball games early. Idk if any of this helps, but i hope you can take something from it. Good luck man