If we drive, my group gets off I-70 at Abilene, goes up to Wakefield, then to Riley, then comes down in on 24. This may take a few more minutes than some of the other routes spoken about on here, but that aggravates me far less than traffic jams and sitting still.
If we fly in, we just look down below and wave at the peasants. 
If you fly, how advance notice do you have to give before takeoff? And, can you easily update your route? For example, if we win can you be like “let’s go celebrate in another city?”
Since I am a private pilot with access to my own aircraft, the only people I have to notify are any passengers that are going with me, and the tower at the moment I'm ready to depart.
If I'm having to go through weather and I need to file what's known as an instrument flight plan (just means a more complicated way of flying because I can't look out the window and see where I'm going) then it's common courtesy to notify ATC of my intentions at least an hour before takoff.
EDIT: Sorry, I realized I didn't answer your other questions. Yes, I am able to easily update routes to avoid areas of high traffic or inclement weather, even mid flight. Also, yes, so long as I haven't been drinking and my friends feel like helping to pay for the fuel, we can watch the cats win an 11am kickoff game in MHK and touchdown in OKC or Denver before dinner time.
