Yi jungle is misleading because he does not have any way to actually fill the "jungler" role. The point of a Yi in jungle is to simply have someone get more farm for the team and then have some damage to contribute to split pushing or baron/dragon. The ganks only work against new people because of the lack of CC, and the new Master Yi is almost worthless in a teamfight because he can't initiate and he can really only play cleanup.
I'd recommend Cho Gath as a good starting jungler. He has good, reliable clears and a lot of CC to offer on ganks. His passive HP gain means you'll have a hard time getting killed, and your CC/damage soaking means your team will love you during a teamfight. If you can knock up/silence their carries, plus 500 true damage from your ult... the fight is instawon.
Udyr is decent because he just has a ridiculously strong jungle presence. His ganking mechanics takes some skill, but if you do master his gankinig the level 2 ganks are absurd with your E stun and the burst from your Q passive proc. He also very reliably fills the role of a bruiser in a teamfight, plus the ability to just whack everyone and stun them all successively is very fun.
Xin is a third really good starting jungler. He heals naturally from his W (so you can avoid health problems), but he also has really strong ganks with his E dash/Q HUGE DAMAGE and knockup. He's another fun person to start with and learn the role. Plus, his teamfight utility is underrated, since a well-timed ult can separate one person from their entire team and result in high amounts of face smashing from your carries.