I just think it's hasty to decide 'this character/actor sucks', much less that it's a day-glo campfest.
It is a very different film from Alien, yes, and was intended as such. And that's fine. But I think it's important to remember also that Scott has said many, many times that his purpose with both films was also to, in the end, scare the hell out of a people. Alien was a haunted house movie, The Texas Chainsaw Massacre in space. The psychosexual elements were trappings, suggestive. Prometheus is also intended to scare the hell out of people, while also play with big grandiose ideas. So if we have a mash-up of, say, Forbidden Planet (which, despite its dated elements, is still powerful, moody, dreamlike and influential to this day, to the point that a very Prometheus-esque prequel trilogy was almost greenlit) and Texas Chainsaw, I'm very happy. Scares and ideas.