Meinshao/anything HJK, Specs Pory Hyperbeam, Headsmash Ramp/Archeops. There may have been a couple additions/subtraction and 'really bad' may be overstating it, but I seem to remember these being ugly matchups in particular.
I seem to lose a lot more in 1-49 than 49+ too Peterko. I blame lack of familiarity with the movesets. =( I share you pain on dozing off and missing trainer types. It would be really nice if they included the trainer name along with the remaining pokemon status display on the bottom screen when you are selecting attacks