Volunteering to tutor students is not usually getting out of your comfort zone. Usually, non clinical volunteering is meant to show that you have dedicated time to helping those less fortunate (ie homeless shelter, food bank, soup kitchen). I would encourage you to try to gain more experience along those lines. You may have to take out service focused schools such as Oakland and Loyola because of that, regardless of MCAT.
Also, UCR and UCD take students near their geographical area. So if you live in the Inland Empire and are applying to UCR, you probably should not apply to UCD as it is on the opposite side of the state. Vice versa, if you are in Sacramento, central CA or some part of Northern California, apply to Davis but not UCR.