I don't know why you're trying to jungle with a music genre, but I would leave Skaa behind.
All of those champions you like are pretty interesting. I feel that Skarner is best suited for the meta at the moment, being that he can use CoC reliably. Evelynn is always going to be low, due to how her clear works. Sejuani is probably not suited for the meta, since she's very easy to invade upon, especially by the current meta favourites of Shaco and Kha'Zix.
Either way, if you find yourself low at the end of your clear, then just back. You should be looking for gank opportunities during your route. A lot of people do the standby of Blue/Red to a small camp, then to the other buff camp, and then look for a gank with double buffs. If all of your lanes are pushed up, tell them to take care for ganks, and try to set them up with vision. (Also be on the lookout for those who have no wards, or look low, or particularly gankable. Those will likely be the ones that get ganked. Try to warn them.) If you can gank, then try to get behind them. Get between them and the turret to prevent them from easily escaping. Doing so that way ensures more of a success rate, and a greater chance of burning a summoner spell if nothing else. Make sure to ping OMW a lot when you're ganking to let your laner know when to go in.
If you can't go in, then just do a full clear and back for items. If you can, try to regen off of Scuttle Crab, since it's effectively free health. As for smiting, try to hold smites for the tougher camps: buff camps, raptors, krugs. You also shouldn't be smiting on your leashed camp, since you can regen with a health pot after finishing off the buff, and your team should have helped you tank enough for that. If not, then just do the easy camps until your smite comes up again.