OP---
I'm in a similar bind...trying to fig. out which schools to apply to. I am a reapplicant, and probably going to apply to about 30 schools. I won't be applying DO just yet.
Here's my 2 cents:
the secondaries --> people are right in saying that these are important and time consuming, however, once you get started and do several, you obviously notice patterns. I certainly did my research on a school before writing a secondary essay so that I knew exactly why I wanted to go to XYZ school.
Also, DO NOT APPLY TO A SCHOOL IF YOU'RE GOING TO WITHDRAW PRE-SECONDARY (unless you are holding an acceptance). It's a waste of money, especially for those schools that send secondaries to everyone. I don't understand why people do this. Fig. out if you're a good fit for that school before paying $30 to apply to it.
Another thing about these secondaries: the best written essays will not make up for weak scores, but they will help if done properly. Secondary essays are not too long, or as open-ended (most of the time) as the personal statement. There's a set question to answer - maybe 1-2 paragraphs, or until you get your point across.
Maybe you should hold off on DO and Caribbean schools until later in the year since their deadlines are further out and also since your #'s are average/fairly competitive for MD schools. Like someone else said, wait and see if you get secondaries from schools that screen, see if you get interviews come Sept/October, and then apply to DO's.
I'm not sure how the DO app. works, but if it's similar to AMCAS in re: to processing, etc, maybe what you could do is submit the DO app early (ie. June), adding just one school just so that it can go through the verification/processing ordeal. Then, later, around Sept.Oct, if you feel you need to apply to DO, you can just add more schools and your app is sent to them virtually instantaneously.
I hope this helps. I'm trying to make up my mind as well since I will be working full-time during application season. I think you should be ok, especially if you're a strong writer.