One thing I've noticed from watching some of my lower league friends (one is bronze 3, one is silver 5, one is silver 3) is that I think it would be extremely easy to carry games by picking a type of carry jungler. I swear about 90% of the games I watch the only lane that is ever warded is bot, and even that's not warded 100% of the time.
Hell, I even watched one of Fris' games (haha, I checked you out on Quickfind and it said you were in a game so I thought I'd spectate it heh) he was Cait + Soraka vs I think it was Vayne + ...lulu maybe? But anyway, there was a rumble top who was carrying pretty hard (his teammate vlad was a piece of shit player) but the rumble was pushed 100% of the time, never bought a single ward til about 12 minutes in. There was an enemy brand mid, never bought a single ward. Yet his jungler didn't really gank at all, just farmed the jungle. Was useless.
The same goes for a good percentage of the games I watch from my RL friends as well. Too many players at lower leagues get pigeonholed into the whole super tanky jungler that doesn't do much damage, yet can initiate and tank well, but at that league a good majority of the time players don't follow up which means your initiation + tankiness doesn't help as much.
I also can't tell you how many enemy junglers I see that don't do Buff 1 > Buff 2 > Gank, they do like Red > Wraiths > Wolves > Blue...I was specing my Silver 5 friend today. Friendly Jungle Warwick goes Blue > Wolves > Wraiths > Red then backs? Almost full health, still like 3 pots left. Enemy jungle was a Hecarim and he did Red > Golems > Wraiths > Wolves > Blue. Like...wtf?
Shyvana, Udyr, Lee, Shaco, Eve, etc etc etc. Steal Kills. Tax Lanes. Carry Hard.