I did all of mine, somewhere around 31 or so. The rest of the schools im applying to have no secondary essays.
I think thats the point, everyone will have a different opinion that includes adcoms. Some adcoms told me they are very impressed by my app and that i have a great chance at med school. Another told me to not even waste time applying as im only average, she doesnt care about what I had to do to get where i am today. I read your PS and i still stand by the fact that I think its great. But others may think differnetly. I feel you explained why you wanted to go into medicine and gave some concrete examples as to why. I mean a great example would be one UCI adcom told me Id have an excellent shot at UCI and the other UCs, another told me id have a hard time getting in to any UC, and most likely id end up getting into a smaller private med school (i.e RFU, nymc, albany, etc etc)...point being youll never please everyone even those who "know" a lot about the process such as adcoms or deans.