@emil Thanks for the reply.
I do think this would be easier for the wiring. However, I would than have to manage 4 schedules to make sure they do not overlap ( lawn and beds on device one and lawn and beds on device 2). Splitting the lawn and bed zones make for nice logical split to manage between the devices and not walk on top of each other.
(pardon the blue tape. those where my notes to translate between the old and new controller(s).)
The two white wires going to the Iro on the left are the common wires. Currently the Iro on the right does not work do to the lack of the common wires.
If we could manage the two controllers as a singular system it would be easier to wire AND manage the way you are describing