Does not giving plasterboard a skim look silly?
I don’t think you’d notice the lack of a skim unless you looked very closely. In my house the plasterboard walls have not been skimmed – the problems came when previous owners tried to remove old wallpaper. Their attempts at removing the wallpaper also removed sections of the paper that covers the plasterboard. So now I need to skim them anyway! In your position, I’d be looking to skim the walls if I could. But if, as you say, money is tight, then I’d just go ahead and decorate anyway, but with emulsion paint rather than wallpaper. Oh, and if you don’t skim, make sure you have ‘Aimes taped’ the joints otherwise they will show.