It completely depends on where you're applying. As Goro said, at some schools your application will be 'reject bait' because you don't have enough clinical experience. Other schools may not care and value your research far more. Each medical school will have a "typical" type of student that they look for, and it varies from school to school. Where I go, the 3 big things they look at are MCAT, sGPA, and clinical hours and I can tell you that no clinical volunteering would almost certainly get you an auto-reject here. If you don't hit a minimum in each of those categories, you get rejected unless you're exceptional everywhere else and can explain why you're lacking in the specific area. Some schools will care far more about research hours. Many won't care that much about either and will just want strong MCAT and GPAs.
To answer your question on "average numbers", here's my opinion. I'd say you should shoot for at least 500 hours total of clinical experience and non-clinical volunteering, and you should have at least 100 hours of each. Research completely depends on the school. If you're going for DO or somewhere that focuses heavily on patient care, then research is just a bonus. If you're going somewhere that focuses more on research, you would want to have a minimum of 1 semester's worth of research but preferably at least 1 year's worth of research to show you were committed to the project. If you're gunning for somewhere like WashU or San Fran which are extremely heavy on research, you're going to want to have either a publication or a few year's worth of research under your belt (preferably both in that situation).
If I remember my profile correctly, I had around 200 clinical volunteering hours, 1,000+ hours of volunteering and clinical experience, ~200 hours of research experience, and 3,000+ hours of extracurricular experiences altogether. I'd say I'd be a decently solid applicant for most schools with those numbers if that's all you're looking at. That's just my opinion though.
