You should apply early to places within your acceptable driving distance to places he wants to/is likely to match at, or you want to go to where he will accept matching. With good luck, you'll have some admits before his list is due.
At your interviews, mention why you like the school for its own merit (you aren't just there for hubby) and then tell them that you husband is interviewing for residency there. That might help you get in, or maybe help you get a decision before feb 21, especially if you nicely tell the organizer who maybe could get your app to adcom earlier (I don't know about this.)
For your husband, he might mention that his wife is applying to med schools adn is exctied by this one. It might help his ranking a bit if they feel that he would be happier there becuase you could be happy there. I was told at one place I interview for residency that they have a big problem with spouses not getitng jobs (it was a remote location) and they were quite interested that my husband had already been offered a job nearby.
Your chances of staying together are increased if he is going into a field like IM where many get their first choice, and decreased with a field like rad onc, where you are happy to match. Same goes for the relative competitiveness of your schools/programs.
I think that this is very doable. good luck! I also suggest scoping the housing scene during your interviews to your top-desired places to save you an extra trip after match day.
