I lived in Ohio for many years before moving to NE Florida and I prefer I-77 too. I drive back to Ohio at least a couple times a year to visit relatives there and we still use I-77.
Besides being a shorter route, it seems that there are fewer large cities, and it seems like there are less large trucks than on I-75. The West Virginia Turnpike is no longer an issue, unless it is during icy conditions.
In Jacksonville, Florida along I-95, I would recommend staying on I-95 and not taking the I-295 bypass around the city unless it is between 3pm and 7pm on a weekday, when traffic can be difficult.
They eliminated the drawbridge over the St Johns River (the second river in Jacksonville on I-95 as you travel south) so there is less chance of a backup.
For informational purposes - outside of the major cities like Jacksonville on I-95, there are motorist call boxes on the side of the Interstates, including SR 528 (the Beeline Xway), placed one every mile. If you have a problem and do not have a cell phone, you shouldn't have to walk more than one mile in either direction to find one.
Another point - gasoline is several cents higher per gallon in Florida due to more state taxes here. If you can, fill up in Georgia before entering Florida. It's about 200 miles from the Georgia border to WDW.
hope that helps