Dude,
I used to live in Missouri (St. Louis not Columbia) and I loved it. How did you do with your prereqs? I think that it's pointless to retake prereqs unless you had grades below a C, you didn't understand the material very well (with a 27 on the MCAT you must have had a decent grasp of the material), or you're shooting for the DO route. I think the better route would be to take more advanced classes (e.g., upper division biology courses) and demonstrate your success that way.
However, if you're willing to go the DO route (there's two osteopathic schools in Cali and two in Missouri) it might be a good idea to retake prereqs. If you retake courses, only your most recent one shows up on the AACOMAS (osteopathic) application. So if you had all Cs in your prereqs and then you decided to retake all your prereqs and received As, only your As would show up. It doesn't take long to realize that you can make a huge gpa leap this way (if you want to see exactly how much, try making a spreadsheet on Excel. But it wouldn't surprise me at all if you went from a 3.27 to around a 3.5ish for the purposes of the DO application, but don't quote me on that). Also, if you're going to retake the MCAT, it makes the most sense to retake the test after you retake all the prereqs.
You didn't mention anything about your extracurricular pursuits other than drinking (which as you know is overabundant in Missouri
) and sex. I'm guessing you won't be putting these down as extracurriculars on your med apps!
While you're working out in Cali, you might want to consider getting in some meaningful extracurriculars as well if you think your undergrad ECs could use some improvement. Maybe you already have enough clinical/volunteer experience and life experiences, but if you're working in Cali for a year and have some free time, don't neglect your ECs.
It sounds to me like this is what you're looking at:
2005-2006: Work in California
2006-2007: Retake all prerequisites
Spring 2007: MCAT (FYI it will be computerized at this time)
2007 Summer: File AMCAS/AACOMAS
2007-2008: Application cycle. Don't forget to do something big here--do research, volunteer, special masters program, etc.
I think your plan sounds reasonable.
Most of the premeds in the postbac forum would not be willing to go this route (myself included) given the choice, but for the time it takes to work in California and retake all the prerequisites, you could already be done with basic sciences in a foreign medical school. Caribbean med students spend their first two years in the Caribbean, but the last two years (clinicals) are all in the United States. Well not all, but for the big ones (SGU, Ross, AUC, Saba) this is true. Make sure you know what you're getting yourself into though--and make sure you know the licensure issues involved (the ones I mentioned above have the least problems, but states like Texas and Cali are a little more strict). Depending on what specialty you're considering, it can be a viable option.
But in all honesty, your stats aren't that bad (some of ours are atrocious) so if you want to get into a US med school it's still a realistic possibility. Just understand that it will require time and effort. Just to give you an example, I graduated in 2004. To reach my goals, I don't expect to apply until 2007 (2004-2005 undergrad postbac work, 2005-2006 hard science one-year masters, 2006- 2007/2008 MPH). So the earliest I'll matriculate is 2008. That's FOUR YEARS after graduating from my undergrad. I realize this is a long time--in fact, I could get an MD in that amount of time!
But four years to get where I want to go in life and achieve my goals is time well spent. For others, I'm sure my plan sounds like pure insanity.
Now my plan isn't typical--you don't have to spend four years unless you're crazy (me). But the point is it does take time.
Another reasonable option, given your stats, would be to enroll in Rosalind Franklin's MS in Applied Physiology program. It's one year and if you do well enough, you can be admitted into Chicago Medical School for the following year. It's expensive, but I think it's the best program if your goal is to get into a US allo school ASAP. Check out the recent threads.
Whatever you choose, good luck!