Just my $0.02. I didn't have a small timespan. I did get married right after undergrad and I start medschool in August; I'm coming up on just about 3 years married. But one of the big reasons (there were a few) I did not apply for the year after graduating from undergrad was that I did not want to put that much stress on a new marriage and I wanted to take the time to invest in my marriage so that it would be rock solid once I needed that level of support.
Having been married for almost three years, and looking back on my first year of marriage, I am SO SO glad I did not get married and start medical school close together. Even if you have been dating someone for a long time, marriage does change things. It is great, but definitely a huge adjustment. The best way I have heard marriage described is that it is just like being single, except that your highs are higher and your lows lower, because there are two of you in the equation.
Because there is a high rate of divorce among medical students, I really felt it was really important to try and get used to that and get it grounded before medical school. That's not to say that it can't be done (starting both at the same timeish), just that for us, we decided to play it safe.
If I was going to wait until after I started school, I think between MI and MII might work, since by then, at least you'll be used to the grind of medical school and ideally your spouse will have some idea of what to expect. Beyond that, between MII and MIII might be better, since that will be the end of your hardcore studying phase and although you'll work some long hours, you'll have a decent schedule for other rotations.
I attached a couple of my favorites since you asked! Do you want to share too??
