I don't see how you can be blaming your Internet for csgo lagging. I got 15 mbps tops (which basically means I got 2 mbps 99% of the time) and never had any issues with lag at all. Either you router is very inconsistent, thus making the actually numbers shown very unreliable, or something in your computer is behind, causing a lot of problems.

Or you're just too entitled to accept any ping at all.