Pretty much my team from my runs that I've done so far.
Emboar: High. With the loss of scald and grass knot earlygame, I feel like this guy doesn't really give much in the endgame. He starts to fall off after Elesa, fire/fighting isn't really a good type combination in BW2 especially with how slow he is and how badly he fares against Skyla (swannaaaaaaaa) and Marlon (jellicent especially). He does have some use in being able to beat Colress and Grimsley, however. The best thing about him is that he's probably the best earlygame starter, destroying Roxie/Burgh with ease.
Vaporeon: Mid/High. An interesting case. Even though Eevee are able to be obtained relatively early in Castelia Park, the Water Stone doesn't appear until after Clay, which means he has a long period of relative uselessness. After that, he starts being extremely useful with his high base defenses and the ability to tank just about everything without dying. Has a relatively wide movepool compared to the other eeveelutions, but blizzard doesn't come until Lacunosa and Ice beam comes even later. This guy pretty much kills Iris (except for lapras) and tanks everyone else.
Krookodile: Top. Same status as B/W, obtained early in game, with a gym nearby for it to destroy with dig. Later in the game, it is capable of pulling a sweep against Caitlin thanks to moxie + STAB crunch. More than capable of powering through many of the ingame trainers with decent 102 attack and 97 speed in addition to moxie with only crunch and earthquake (or dig)
Jolteon: Mid. While obtained early and also not taking long to evolve (*cough*vaporeon*cough*), it has favorable matchups against Skyla and Marlon, but only learns signal beam and shadow ball for coverage. While it may seem like a great Pokemon due to having 110 spattack and 130 speed, it is severely outclassed by magnezone (like all other electric types), who is far bulkier, resists more and has better coverage with flash cannon, which is enough to outweigh the dramatic drop in speed.
I'll do more tomorrow when I'm actually on a computer.