Hi Zombie,
I've run the gamut from Bronze 3 to Silver 1 this season (currently S4). That's my way of saying I'm just about average at this game, statistically. However, I do think I can help point you in a few directions that might improve your play. Nothing on specifics but more relying on macro information that I've gotten about you from op.gg.
The one major issue (data wise) I notice is that your KDA is fairly low. It's only above 3.0 on one of your 7 most played champions (Amumu). You should focus on improving this, more so on reducing your deaths. As obvious as it seems, each time you die you give the enemy team gold. If you are dying more than you are killing (which is the case for each of your top 7 most played champions), you are putting your team at a disadvantage. This is because the net gold is still in favor of the enemy team. Further, deaths matter a lot early game because it helps the enemy team build those items which will snowball them later. Thus if you die in ganking a lane then that laning enemy still gets gold to buy an item, even if you killed them. At best, they are now on par with your own laner, at worse they are ahead if you got the kill and your laner got the assist.
In short, reducing your deaths might be a worthwhile step. How you do this is up to you. Perhaps just avoid situations where you may die (e.g., gank less). Because even though you say you are focusing on ganks, you may still be dying more often than not during those ganks.