I think part of the unearnedness comes from how rushed the ending was and while we got no real explanation for Paul signing up at least there was a whole scene giving some indication of the the bargain he thinks he's struck. All we see of Echo is her back in the box. But I'd be fine with these things being fleshed out in S2 or even hinted at in the mythical episode 13.

Alpa was a very Caliban-like character to me, I didn't see him as simply crazy just that crazy was definitely part of the mix.