*shrug*
Having been an actor, I thought the acting was pretty good, but I'm likely not the best person to ask as I tend to cut some slack to actors early in any series when they are still working on who the character is.
As for plot holes, dude, it's Week 1 of an Abrams mystery based totally on fiction. It's Fringe, just with a different premise. There are supposed to be holes. And as for the "ridiculous premise"...I'm guessing you don't like Dr Who either, huh?
It may not be for everyone. No worries. I don't understand why half the stuff named in this thread gets the time of day from anyone other than just chalking it up to different strokes for different folks.