AD Shaco which is the common way Shaco is built is somewhat useless. You can't really gank unless you put a box behind the enemy, though they can usually walk around it with ease when they see it, and Shaco has just pathetic damage output lower levels if you don't backstab the enemy constantly.
AP Shaco has better clear times but plays a Teemo-like way and loads boxes into a bush or area, lures you into it, lets you take averagely about 130 damage per second (per box), Q's behind you, and then E's/Smites to finish the job.
Shaco needs to have his AD increased, playing him with AP is difficult but really powerful for taking 390 damage per second (With 3 boxes) on top of a fear and an actual way of executing the enemy. He's probably one of the hardest junglers to gank with at the moment, whereas some junglers such as Diana and Warwick gain extremely good ganking abilities at 6, Shaco doesn't. I think Shaco is more of an objective controlling-split pusher if played AD (or AP because the minions or enemy champions can trigger boxes to attack objectives including turrets, nexus, and inhibitors. Though this is VERY difficult to set up because the boxes can always attack the enemy.) due to him being completely unable to be in a teamfight, where he does have good dueling capabilities and maybe one of the best in the game just due to his capabilities to turn the 1v1 into a 3v1 with his clone and boxes.
Shaco in my opinion is a very early and a late game champion. Early game he has the fastest initial clearing in the game to the point where people can't leash him or they will steal his experience/gold, and he usually follows it up by stealing the enemy buff directly in front of him. Though in terms of ganking he falls off hard since the most he can do is smite the enemy for a second and attack them until they walk under tower. Late game he gains power with items and is able to very quickly assassinate squishy targets.