I agree with BluMist - being an ER scribe is plenty of clinical experience, and with your history of being a CNA as well I think you are maxed out on the benefit you will get from having lots of clinical experience. The time spent on that endeavor will be unlikely to boost your application more, and would be better spent on other endeavors. Trust me - from my discussion with adcoms, this can only bolster your application so much, and won't cover a large blemish in your record.
That being said, because you're asking for ideas, here are some that I tried when I was trying to get experience:
Reach out to doctors and NPs at local clinics and tell them you are applying to medical school, and that you'd like to shadow them. Volunteer at a Free Clinic - they are happy to have helping hands, and you can see a lot. I know there are impromptu weekly free clinics in Chicago associated with some of the larger homeless shelters. I've also had success reaching out to the AAFP for connections to doctors who would be willing to let you shadow. Stay away from asking academic institutions - they are stricter about HIPPA and won't let anyone not officially in training near a patient. All hospitals have a volunteer office that will let you get involved as well, although most of them do basic candy striping stuff.