Definitely use the RO water.... Hard water is a disaster for beer like this. The basic additions you have above will get you in the ballpark for sure. It will provide a good base for you to start with and you can tweak it more from there if you want.
I have been bumping up the sulfate in a couple recent attempts and really like it. So, something you might want to try in the future to compare it to would be to do 1 tsp each of both gypsum and CaCl in both mash and sparge. Or, reverse the gypsum and CaCl additions with more gypsum and less CaCl.....That would give you a second and third variation to see if you have a preference between them.
Thanks for the information. I had a feeling something would go wrong with my brew day tomorrow. I just got home from picking up my ingredients. I was given green bullet hops as a substitute for Galaxy and calcium carbonate instead of calcium chloride.