I like the pouring spout lid I got for the paint can a while back. You can just switch it to whichever can of paint you're using at the time and avoid dripping down the outside of the can or having paint pool around the lid channel. I hadn't seen this one, or I would have gotten it instead.
I think it came out pretty well.
I think I'll tackle this window next. I need to fill nail holes with wood filler and do some caulking, then I can paint the trim and ledge. It's a nice depth for plants, but this is facing almost due north. We get some direct sunlight in the morning but that's it.