Sounds like you got skills…. Open Sprinkler uses open source software. Maybe you can contribute to the software by adding the program features you need, then the whole community would benefit.
I returned several other brands of ethernet sprinkler controllers due to them being way too limited on zone and programming control. I saw OS is able to do most of what I want and that it is being actively developed so I went with it. I would love to have the detailed features you are talking about. Then OS would be a perfect choice for any irrigation needs, and would blow big commercial irrigation controllers out of the water.
Maybe OS could be preloaded with two different UI? One being for people who mainly use it for yard sprinklers and have a simple UI, and the other for a more complicated precise total control UI used in agri irrigation.