I applied to some of the same schools as you (in Illinois) this cycle. Did you ever hear back from Elmhurst? The one thing I really liked about this program is the fact that they seemed to look at the applicant as a whole, not just GPA.
From what I remember of Depaul, they will still consider you if you are enrolled in or plan to enroll in your remaining prerequisite class. They also have winter cohorts, so it may be worth registering for OChem and reapplying for this winter. Also, I would consider applying to the Rosalind campus because the Lincoln Park campus filled up much faster, so it might be a bit more competitive.
It's possible to take more GPA boosting classes, but some schools look exclusively at the GPA of your undergraduate degree. If I were you, I'd probably focus on taking the prerequisite courses needed to apply to more programs. Also, I'd look into other programs and apply to as many as I could. I've heard Milkin has a good program that looks at the applicant holistically. In addition, your GRE scores are average (a little below in the quantitative), so that could be a relatively easy and inexpensive area to improve upon.
From what I've heard, PA school is very competitive, so it may be more difficult to get it.
You were waitlisted, which is still a good thing! I wouldn't give up just yet. Take more classes that will open more doors for you and apply to more programs. Also, getting more patient experience would be a good thing as well. You could take a CNA class or look at volunteer opportunities. I know there is a program in Illinois that looks for volunteers to sit with hospice patients.
I'm new to this whole process myself, so take my advice with a grain of salt! Good luck! I hope you get in somewhere :)