I would never paint clay roof tiles, and dark trim does not really go with that house style.

I would never paint the roof tiles either. If you want to change the paint color to a lighter cream color, that would look fine, even though, I think what you already have looks very nice, with the exception of that stark white garage door. That should be painted the same paint that is on the house.

A warm cream with a brown like urbane bronze (check if it goes with the roof or you need another shade) would tone down the red of the roof. You don't want to paint the roof. It won't last long and when it starts flaking, it will look horrible and you won't be able to get the paint off.

You need some more plants. There are a ton of beautiful options. Go to The Plant List : The Arizona Native Plant Society. Or go to the search bar on Houzz and search for Arizona landscaping photos.