It probably is not realistic to work more than about 10 hours per week while studying a full course load (particularly if you have lab courses), unless you plan to do nothing but study, work, eat, and sleep.
Since Minnesota is your low cost option, it would be good to consider. The possibility of not getting into the major if your GPA is not high enough (3.2 is high enough, lower GPAs can gain admission on a space-available basis) is a concern. However, if your major is top priority, the escape hatch in this case is to apply to transfer to another school in the major, such as UCR, CPP, CSULB, SJSU, New Mexico Tech, or South Dakota Mines (these schools are not that selective for transfers and not that expensive).
Or just go to one of your UC options where you are already in the major and not worry about either cost or getting into the major.