It's all normal...not that that diminishes any of the frustrations you're having, but at least you know it's normal and you are certainly NOT alone!! Keep redirecting until you're blue in the face. Move the nightlight so he can't get it when you aren't around. Continue doing time out, don't worry about it if he's having fun while he's there. The point is to remove him to the situation and you're doing that, he doesn't really get the ins and outs of time outs yet, but the fact that you can stay consistent with them will help.
My son is 19 months and we are dealing with most of these same issues as well. I asked my pediatrician about holding him in time out as well and he said go ahead and put him in the crib that I shouldn't hold him there. Although, I do sometimes if we're not at home and I think it's fine. Do what works, stay consistent, that is what will make the biggest difference I think. In a few more months things will get easier...hopefully! ;)