We love the I90/I79/US19/I77/I26/I95/I4 route. It is quieter and beautiful. If we were driving at the end of Feb., that would still be our preferred route, however we would be watching the weather and if there was going to be stormy weather in that area, we would probably go for I75 or take a route to head all the way over to I95. I think in the winter you have to be flexible and take the safest option.
The first time we drove as a family, in January 2005, we left at 4 am and it was perfectly clear until the snow started falling at the NY/Penn border. It was coming down hard. We went as far as just before Pittsburgh and got a hotel. The snow stopped in the evening, and when we left the next morning at around 8:30 am, the roads were in pretty good shape, even through the mountains. After Beckley, WV, it was warmer and clear sailing. Since we had a good rest the day before, we drove all the way to our destination in FL (arrived about 2:30 am, making minimal stops). That way, we didn't lose any actual vacation time.
The I75 has mountainous areas as well, and there can be heavy fog as well in some areas.
Good luck with your decision.