Keep the Air Compressor
"I'd vote downsize the air compressor, unless you spray a bunch......"
An Air Compressor is my 2nd most valuable large tool after the Table Saw.
Not only for spraying but also for air sanding. I find air sanding far superior to an electric sander and also for blowing down the shop everyday before clean-up. A Pancake air compressor is only good for nailing.
As for the planer, thats another story. I dont own one now and buy all of my hardwood lumber S2S. Even when I had a 5HP 12" planer, I still used to buy S2S. For the small additional charge it wasnt worth it to me to plane everything. It all depends on what kind of work you do. A planer is pretty high up on my list of things I really need but I'm not sure of what size. I think I will end up with a 24" drum sander and a lunch box planer. as opposed to a 20" planer and a small sander. I build furniture so my requirements may be different than yours. I also am tight on space and money so I cant have it all.
Retired, living and cruising full-time on my boat.
Currently on the Little Tennessee River near Knoxville