vivacium, there’s a lot of things you can do besides research for a year after college that is medically related. Work as a volunteer at the clinic, hospice, rehab or nursing home. Join your fire and ambulance corps - there’s nothing like extracting people from their cars after DUIs. Get an internship at the public policy organization or nonprofit at which health care policy is their focus. NAMI, for example, in DC. Or an association for a clinical specialty in which you have an interest. It won’t be a wasted year - it’s a year to add depth and breadth to your interests.
And no one underestimates the ability of students to work hard and juggle competing demands. The point is that ALL pre-meds do this routinely, so it’s not like you will have excess capacity to ramp up your efforts. On the contrary, this is where students routinely crash and burn - they over-estimated their own capacity relative to their pre-med peers (the comparison group is NOT the average student at your school.)
And yes, majoring in bio or chem will help a great deal by cutting down the number of classes you have to cram into your schedule to graduate on time, while still giving yourself time to study for the MCAT, do the required research and volunteering, and do the interviewing once your application is in. But taking the extra year is the way to ensure that you do all this without burning yourself out before you even arrive at med school.