League of Legends: Better?

A couple months ago I posted about trying to get better at League of Legends by focusing on properly farming minions in the early game. At the time I was running at about 60% of a top player in terms of creeps killed in 20 minutes and in termed of how much damage Nasus' Q ability did. (That ability permanently gains 3 damage for every unit killed by the ability itself.)

I've been playing a fair bit with Robb recently and we pulled my rating up about 400 points from its low point which is a pretty substantial amount. Was that just avoiding the terrible match-ups in 'Elo Hell' or are we actually getting better? I've been noticing my minion kills have really gone up in the last little while since I bought the hero Graves but maybe that's just the hero (compared to Vayne and Tristana)?

I haven't actually played Nasus at all recently but last night I made a point to play him in a game so I could have some numbers for comparison. I was probably a little rusty but a lot of the basics are the same...

After 20 minutes
Nov - 94 creep kills, +189 on Q
Jan - 123 creep kills, +237 on Q
pro - ~150 creep kills, +~300 on Q

This is obviously a really small sample size (one game each time) but that's a pretty reasonable boost. Up from 60% of the pro to 80%. Now, I'm also not playing against pro quality opponents so it's not as good as it may sound but I think it's showing improvement from caring enough to focus on it the last two months.

An a not even comparable data point, here's what I had on Graves in a recent game where I laned with Robb as my pocket healer...

124 creep kills after 20 minutes which is about the same as Nasus, but up 70 at the 39 minute mark (when the Nasus game ended). I certainly did a better job of finding anything to kill during downtime when I was playing as Graves. I think part of that might be team role though... People stand back and let Graves kill stuff. No one lets Nasus screw around killing things when they could have them instead!