Made a post below, but... I'd say that maybe Yes. (Gaming)

by Korny , Dalton, Ga. US. Earth, Sol System, Thursday, November 10, 2016, 14:33 (2728 days ago) @ MacGyver10

Would you say the single player campaign, as good and short as it is, is worth the $35 alone?

- MacGyver10

Knowing Cruel, he'll definitely say that it is.

I think it's a really fun campaign, and though I've only played through it 1.8 times, I still had plans ti play it again. The vast majority of Trophies/Cheevos are single-player, and most aren't that difficult to get.
As someone who didn't really like the first game, and who isn't willing to get the whole package for $60, I would say that you should definitely pick the game up for $35.