If you do take I-70 from Columbus to Indy, once you hit Indy it's best to head south around the beltway to get to I-74.  I've gone the northern side, but seems to be lots more construction up there the past few years...

If you don't particularly like interstate travel, you may not want to go this way.  But you can average 70+ with a canoe on top just about the entire way to Duluth so it's a bit faster route...

Two years ago, I headed north from Madison to make a pit-stop and replace a rod at the St Criox shop in Park Falls, WI.  It was actually a very nice drive from there north to Ashland and then over to Superior....