AzChad,
The flex daily schedule is the one you want to use. It will monitor the weather and add up the daily water use of the plant material until it gets to the allowed depletion amount and then it starts the watering. You should allow it to happen any day it wants when using this schedule, especially with drip because you aren’t worried about watering on a mow day like you are with grass. For grass you would want to create another flex daily schedule for those zones but then put in the one no water day for the day you normally mow the lawn.
For Gilbert you want to select clay loam as your soil choice. Clay loam has a high water holding capacity so it does go for longer periods in between watering than courser soils like sand.
Selecting the proper root depth will be important too. Normally here we tell people to water shrubs at 18-24" deep. However in watching how the Rachio controller accounts for the water use at that depth it goes for very long times in between watering. I would suggest setting the root depth to around 12" for shrubs and 18" for trees as a starting place. If you had been previously watering very frequently before installing the Rachio you may need to start out at a shallower root depth to begin with and then adjust it deeper incrementally after monitoring how well the plants are doing to make sure they have the roots to take advantage of the deeper less frequent watering. At this time of year for established desert adapted shrubs the recommendation is to water them about once every 21 days. High water use shrubs would be watered a little ore frequently, around once every 14 days.
The first thing I would recommend is changing out the micro bubblers, what you are calling adjustable emitters, to pressure compensating emitters. The micro bubblers can apply the water at very high precipitation rates. With our clay loam soil that is not good because trying to water longer for deep roots causes the water to run off, it will not soak in. The micro bubblers are good to use for flower pots and such which have very loose soils.
The other reason to get away from the micro bubblers is that you don’t know how much water is coming out of each one. This makes calculating a precipitation rate impossible. You will always have more pressure at the first emission point on the zone than you do at the last one. Pressure compensating emitters put out the same amount of water in a wide range of pressures.
As a Gilbert resident you can also contact the water conservation office at gilbertaz.gov/water and set up an appointment with a conservation specialist that will come to your home and help you with these settings based on your landscape and your irrigation system. The first thing that will be recommended is to install pressure compensating emitters.