It won't be any better the second time around... the CG are a bit dated now and it's tough not to pick on them a little bit. Maybe give the commentary a go and then try re-watching it. It won't be any scarier but maybe the insight gained from the commentary might make it a modicum more interesting at least.
Yeah, I'm still harshing on it. It's not much more than a cobbled pastiche of better scifi/horror flicks. I can see all the influences. The character arcs aren't really handled well. Considering it only clocks in at 1:25 or 1:30, it seems like a bunch of stuff was tossed in the edit room too.
Plus, I didn't really find it scary. Just dumb people doing dumb things or having random awful things happen to them without much coherence. Sometimes that can work (like Nightmare on Elm Street sequence) if the film is self-aware enough to not take itself seriously and/or focus on the dark humor instead, but Event Horizon isn't that film.