Fall is my favorite time of year to ride. The cool/cold weather can be negated by proper attire. I've ridden to the low 20's (F) as long as there is no snow. Some day I will try snow riding... some day. I also have lights (front & rear) for night riding and enjoy that too.

Now is the best time to buy. You'll get great deals if you find your size. You should also look at used on Craigslist.