Kerrigan and Tassadar of the Jungle
Last night I played around with jungling builds for Sarah and Tassadar in Heroes of the Storm, and found that with full health and mana, Sarah could safely solo most camps about 3 levels ahead of schedule. She's particularly effective against the knight stacks as she can stack and the AOE stun them. Only Arthas has a comparable farm but his doesn't kick in till level 10.
Where Sarah lacks vs Arthas on farm potential is she is much more open to ganks. When you spot Arthas jungling, it is always tempting to snipe his kill and steal the stack. A well positioned grab and stun can buy you enough time to grab it. But if Arthas finds you at the same position, odds are you're just dead. Part of this is due to Arthas having decent AOE damage overtime, but more due to not being all that mana hungry. Given Arthas's ability to regen mana, he has the definite edge in the jungle.
Tassadar is totally on the other end of the spectrum. I am amazed at how much staying power Tassadar has. He is the tankiest support in the game by far, and can totally turn a team fight around. By end game, he can pretty much maintain a permanent shield on an ally, and escape most attackers through damage mitigation and slow.
In the jungle, Tassadar is surprisingly effective even though his AOE and auto attacks tickle. The key tactic is Tassadar can evade the stack by popping Void Shift, resetting the aggro, and allowing him to re-engage on his own terms. This makes it hard for Tassadar to die by overcommiting to a stack kill. He doesn't even have to run away, making it less likely to draw the attention of wandering opponents.
But where Tassadar shines as a jungler is his Oracle ability makes him largely immune to gank attempts while fighting a stack. In fact, I found he's great for counter gank / stack steals. Even though he's a tickler, his endurance makes it easy to lock down an opponent long enough for help to arrive. With decent map awareness and the ability to tank a ton of damage, Tassadar can be nigh unkillable. In the course of 3 matches, I totaled a single death, and it took a 3 man gank after jungling a stack of knights. I’m pretty sure had Oracle not been on cool down, that death could have been avoided too. Overally, Tassadar in his current form will probably be nerf’d hard.