I tried to avoid using 20/20 hindsight on this question. For example, I think it is 20/20 hindsight for me not to take Human Anatomy because a few schools didn't require the class. However, I wasn't aware last semester that I would get as many interview offers so late in the application cycles so I would have taken it anyway even if I applied early. So, I would have...
1. Applied Early = not for Spring slacking-off's sake, but I would have had less stress had I been accepted earlier
2. Apply to more schools = I screwed up applications to good schools like Auburn and UF while missing the PharmCAS deadlines to other good schools.
3. Prepare better on my interviews = Though I think I did well on all of my interviews, I should have practiced my delivery more.
4. Get more pharmacy experience = My lack of pharmacy experience was the weak link in my application. Even if you had told me that I would get interviews, I felt that I could've screwed myself w/o pharmacy experience. Fortunately, it didn't make a huge difference.
On a side note, if you got into the school of your choice, then I wouldn't change anything at all. This comment comes from the Trekkie side of me where making changes in the past to better your future can backfire. I got into one of my top schools, and there were schools I would have strongly considered had I applied correctly, but changing the past could be disastrous if something weird happens and I don't get into any school.