I'd take the 74/275/75 route around Cincy rather than Louisville. Even if the delays in Louisville aren't as bad as expected, I-75 is generally a better road in Kentucky than I-65. It has more 3 lane sections than 65 and usually fewer construction headaches.
A note of caution, though: between Lexington and Richmond, KY on I-75, there was a bit of 1-lane road at times this summer during what should have been simple road repaving. I don't know why it took so long or if it's finished yet, but keep a watch out. Also, we noticed last weekend that they're getting ready to, I think, 3 lane a currently 2 lane section of I-75 between mile markers 58 and 68. They may close one of the 2 current lanes at times there, but fortunately that isn't as crowded a section of road as the stretch between Lexington and Richmond. Even with these cautions, it pales in comparison to the seemingly constant stories I read/hear about much of I-65 being a parking lot at times. If you get stuck in a jam on I-75, you can usually take an exit and get on Highway 25, which runs parallel to I-75 through much of the state, and has many entrances/exits on I-75.