There are only a few reliable junglers at this point. Jungle is a nightmare to play on 90% of the champs. Most champs all you have to do is send in mid or bot once or twice early to invade jungle and the jungler is out, especially in low elo where nobody rotates or helps. There are a few junglers that need to be toned down, but I think it is more the champ type, as those particular champ types are really strong over all.
Jungling is the most thankless and flamed roll in the game.
*pushes lane all the way to enemy tower with no wards, gets ganked, flames JG
*pings for assistance while jungler is on the other side of the map, gets killed, flames JG
*Jungler gets invaded by whole team while other lanes don't even ping mias's or rotate to help, flames JG
I could go on.....I think the biggest problem, is most people in the game other than the top levels, do not know enough about junglers or how to play with them in the game. There are some amazing vids on freezing lane and warding that make most JG champs obsolete.