From what I've heard (my friends in my med school who are WA residents), UW is notoriously hard. I had friends try for 2 years (with better stats than yours) to get in to UW, told they'd be great candidates, and they didn't get in when they reapplied.
This is very similar to my own experience. UW was my top choice the first time I applied to medical school. I moved to Seattle as soon as I finished undergrad, became a WA state resident, spent a few years working as a researcher at UW Med, filled out my EC profile a bit more, and applied to medical school. I made their in-state interview cutoff based on my GPA and MCAT score, and thought that I had a pretty good shot at admission, based on my vested interest in and work history with UW, and the fact that my PI and another professor at the medical school wrote UW-specific recommendation letters that went directly to the Dean of Admissions. I was also ecstatic that I was extended an interview so early in the season (I believe it was in August).
My interview was a nightmare (3 on 1 format, with one of the interviewers being a very sleepy 4th year, and another an over-the-top argumentative PhD-type who no doubt was trying to rattle the interviewees' cages by disagreeing with every single answer), and I was told point-blank at the conference table that I was "too highly opinionated." Lame excuses aside, I was a bit disappointed in my performance but nevertheless held onto my high hopes that my work history and strong desire to remain in Washington State would demonstrate how committed I was to UW.
Not even 3 weeks later, I received my rejection. I was devastated. It meant that I had to leave town.
Oddly enough, I am now at Maryland. (Maryland is my official "home state," and it wasn't too hard to re-establish residency here once I moved from Seattle.) I completely understand how you feel - I really do love Washington. I didn't want to leave. I missed having my established social network, my favorite spots, etc. It was difficult to return to an area with which I have a very long-standing love-hate relationship. Baltimore is no Seattle, that's for sure.
However, you have to keep in mind that there are no guarantees. I was certain that I had a decent shot at UW, and they slammed the door on me. You may think that you are sitting on top of a winning lottery ticket ("if I just apply a little earlier next time..."), but everyone feels that way. It would be extremely foolish to give up an acceptance to a school because you are speculating that you *might* have a good shot at UW next cycle, regardless of what the Dean told you. Unless he outright offered you admission to next year's class, nothing is guaranteed.
Take the sure thing. I learned to adapt to life in Baltimore, and I really, really love my school. Maryland has graduated students who have gone to UW for residency, so it is possible to return to the PNW. Unless you would be going to UW on full scholarship, I believe that your estimation of the cost difference is a bit off. And, if your screenname is reflective of your personality, you will fit in very well at Maryland.
The only way that there would be any real "decision" to make is if you had been guaranteed admission to UW. Since you haven't, what's the point of speculating about something that you don't even have?
Good luck.
Edit: A little perspective - You got into medical school. Off of a waitlist. In June. You should be jumping for joy, not having regrets. You're going to be a doctor. There are people who would kill to have your spot.