I know at the end of the day you got to establish your own rep but two things about Eugene beating up Little Pauli at the site for busting his balls: you think Eugene wouldn't have come at him or at least not nearly as hard because he IS Paulie WALNUTS's nephew; and why DIDN'T Walnuts retaliate against Eugene for his nephew as he did against Christopher (who's certainly higher up, closer to Tony, than Eugene) in the later episode, Walk Like A Man? Anyone else ever wonder that?

Yeah I wondered that. One possible answer could be that Little Paulie wasn't yet a made guy at the construction site, as that was season 5. When the thing with Chris happened he may have been a made guy as it was later on. The severity could be another thing, I mean, Eugene did fuck him up pretty good, but Chris could have killed him, and almost paralyzed him.
Another possiblity is that, like at other times in the show, the writers either A, didn't realize the inconsistency or B, just didnt give a shit.

Yeah, when Gene Pontecorvo roughed Little Paulie up, he wasn't a made guy yet.