I do not mind "sucking it up," but winter has not been kind to me. I normally train in winter (I do not sit it out), and do not even mind cold weather. In fact, I enjoy coming home to a warm house after a cold day's run.
Two winters in a row, I have had high hamstring/glute issues, one year on the right side, and one year on the left side. These are difficult, annoying injuries. I took some time off, but "ran through" some of it, as I longed to get back on the roads. I hate sitting around.
When the temp gets below the upper 20s (F), that is where I sense the problem is. I hate the heat/humidity, but January and February are the toughest training months here, as at least I have not been injured when the weather is warm or hot.
I live in a hilly area in Virginia. As far as the expense goes, I have checked some hotel rates and they are similar to what I paid in NYC. Many of the better choices (closer to the start) are already booked. The race itself is a little cheaper, but I did not pay the full $255 for NYC, as I am a veteran. I think I paid $215.
Yes, the race is flat, but I also checked the historical weather, and it looks like one will find plenty of wind on that course. I have friends who have run it, and they mentioned the wind...but they liked the race overall.