If you’re more comfortable with frequent, shorter duration watering, Rachio gives you the freedom to do so.
Under Advanced Zone settings, the key parameters to decrease water duration and increase frequency is root depth (duration and frequency iirc) and nozzle in/hr (duration). For your bushes, if you selected Shrubs as the zone type, the root depth will be set to 15 inches. Reduce the value until the durations reach what you’re familiar with such as 6 inches. The other setting to check is the Nozzle/Inches per hour. The default may be low which would cause watering times to increase. For drip, there is a Community post that explains one way to find nozzles/in hour. In any case, observe your plants and adjust as needed; nothing magical about Rachio – can’t figure out the plants and irrigation system without help 
https://support.rachio.com/hc/en-us/articles/115010542148-What-are-Advanced-Zone-Settings-