Since hushcom is taking a break, allow me to chime in:
Tutoring and getting paid for it is a job.
Tutoring for free is an altruistic endeavor.
I'm OK with it.
1. How much would it hurt an applicant if they have a couple of semesters with class loads just below full time, say 9 to 11 credit hours, if the applicant has a 3.9 or better GPA and heavy (13 to 17 credit hours, and 8 in the summer) upper level science course loads during their senior year to compensate?
I don't pay much attention to TA'ing when this activity is listed.
2. What is your opinion of TA experience in upper level science classes? How useful is that on an application?
Plays no role. We don't care about majors or minors, only that you do well in them
3. How much does college major influence your opinion of someone's GPA? Specifically, is there a significant advantage for someone with a major in chemistry vs. biology vs. liberal arts major if they all have the same GPA?
LizzyM defined much better than I did, but it boils down to your helping enrich someone else's life. Serive for others is looked very highly upon. My particular soft spots are Habitat for Humanity, military service, TFA, or any teaching at the public school level, Americorps, Peace Corps, volunteering in nursing homes, camps for sick children or hospice.
4. What are the most important factors you look for when analyzing the significance of someone's ECs, both medical and non-medical? For example, I've been told that many adcoms value "quality" of the experience over just racking up a bunch of hours.
Knowing what the soccer coaches have to go through with my kids' soccer league, I'd say this is very altruistic. Church-0based helping programs are fine, missionary work is not as valued.
Does 5-6 years of volunteer experience in youth sports coaching and church-organized community programs provide a solid non-medical volunteering background?
I will disagree with my learned colleague on that one, but you should have a LOR from your PI prooving you were int he lab and contributing.
5. You mentioned earlier that research experience is not very valuable if there were not multiple publications. Does this mean that a year or two of research with only one pub is virtually useless?
This will probably depend upon the schools you're aiming for. Keep in mind that it's a seller's market and so MD schools can afford to turn away many highly qualified people. On the other hand, people with a non-trad background do get cut some slack. BUT, MD schools also view MS or PhD grades with suspicion, because of the high degree of grade inflation in grad programs, and the nature of the classwork doesn't mimic the rigor of medical school classes. But people do get into MD programs with MCATs in the high 20s, but you can likely rule out Harvard or Stanford. key thing will be to apply strategically.
I'd like to get your opinion on how MCAT scores are viewed for non-traditional applicants with graduate degrees. A little background...I'm a 34 yr old caucasian female E01 applicant with a PhD in biomedical sciences. As you can imagine it has been quite some time since I've taken my under-grad pre reqs and although I have a sGPA 3.75 and cGPA 3.8 I fear my MCAT will be in the high 20's due to working full-time and being years out from my undergrad courses. Do adcoms take these challenges into consideration? Does having an advanced science degree (3.95 GPA) help my chances at overcoming a lackluster MCAT score?