Thanks to both of you for responding..
All the heads work and are adjusted best they can be. The issue with my yard and most suburban irrigated yards is that the heads and measurements are not hydraulically engIneered or modeled. It is a landscapers quick work. The sprinklers are not terrible but coverage is not perfectly even within zones. So I have to plan for the lowest common denominator.
I do tailor my zones to the specific sprinkler head types. But rotors have always been too low. Good tip by @robertokc that the standard rotary assumption by Rachio might be high. I can't identify the heads I have because I moved in 15 years after they were installed. I doubt all the heads are original today. I will try but think even if I can find a unique model it might be hard to find flow rates from 15 yrs ago and some may be adjusted down some anyway.
Like I said, today I'm just doing Fixed Days. All I really want to do is follow Rachio climatic / seasonal changes and maybe adjust the zone + / - percentages to dial in the standard to what I see as proper. Is this possible? Do you have to dink with head flow rate assumptions to get this zone specific + / -?
I'm not going to be wasteful, but do not need to micromanage water usage where I am at. Flexible daily doesn't sound like its for me based on the app description. Flexible monthly sounds interesting as I have 1/2 grass zones and 1/2 flower bed zones and the beds need daily watering (but not much water at a time).