I've ridden the Natchez Trace Parkway in mid-March for spring break. I started in Nashville and headed south. It was cold and cloudy and by day 2 it was about 40 F and raining, some of the worst touring weather I've experienced. It was snowing and freezing rain just north. It was my only week for spring break so I just dressed as warm as I could and rode. I was staying in hotels, so as long as I had a hot shower and warm bed at night I was OK. By the middle and end of the week as I got south it was 60 F and sunny and felt great. I met other bikers along the way that were camping every night. I remember thinking, they are really stupid or really hard core. Bottom line is, its totally doable, just keep an eye on the weather, dress right and be flexible. Plus if you have sag support, you can just bail out any time if things get real bad. I think the NTP is more bike friendly that the Blue Ridge. Just as much seclusion, fewer hills and you don't have to go as far off the Parkway to finds services. Be careful around Jackson and Tupelo during rush hour and on the weekends, more cars. But most of the time you forget its not a bike trail because cars are so few and far between. Enjoy!