You may regret swapping out for a smaller A/C in another year or two. I know I'm glad I upgraded mine (13,500 to 15000) and wish I could upgrade even more.
But there are smaller ones (others have pointed) you might also, if that Robi can be "Twinned" and parallelled go that route. Makes it possible to use electric coffee maker and A/C at same time (Or other kitchen stuff)
Just now I'm on a well shaded 50 amp site so for the first time in a while I'm staying cool all day. No sewer (But I won't be needing to dump till my next stop and that will be full hook up) but nice and cool!!!