I gave it some thought - since as ForeverLaxx said, ive been hopping on whatever champ bandwagon seemed the most crowded at the time - and figured out what im worst at in terms of who my champ should be to help balance it - early game. Granted, everyone's bad to some degree early game simply due to lack of items and ults and whatnot, but i tend to overextend or not be aggressive enough.
Usually, assuming the lane isn't going well or i get ganked, it's for one of three reasons:
1) I get a foe down to low health and try to finish as they retreat into turret range, i try to make the last few hits and duck back to safety, but fail.
2) I get a foe into the red in health, only to have another foe leap from the underbrush (most recent was fighting Nasus and Pantheon jumped from nowhere)
3) I realize my range isn't enough and stay back when they approach, but they just feed on the minions until they can blaze through mine and then me.
Funny thing - going into the game, if asked if chasing into turret range for a kill is smart, id say no, survival > kills, but that fact escapes me when i actually have a chance at a clean kill and survival if i can dash in and do the damage before the turret takes me down.
Anyway, back to the issue - I'm not dealing sufficient damage to them - they keep running out of range, which is an obvious response you can't stop, but what if there was damage they couldn't stop even once in the fog again? The thin line is my issue - either too much health and they stick around to harass, or too little and they wise up and flee early to turret - I need a hero with DoT abilities - a few come to mind - Gangplank, Teemo, Brand, and Cass, but im not sure which is best suited to DoTs specifically as opposed to just having them - judging by Core's comment, Cass is, but I'll stick with GP while he's still free to see if i like the whole "run in, stick a DoT, run out, repeat" cycle.