Where is everybody getting their tickets? Through K-State? Secondary market? I assume K-State’s sections will be on the visitor’s side, right?
K-State allotment sections are: 136-139, 142, 240-244, 442-446. Given the small size of the TCU fanbase and K-State being 8 hours away, my guess is that if you buy in the upper deck, you'll probably have plenty of room to move around. I bought tix on Stubhub a week ago and there were loads and loads of options at all levels.
As for things to do, skip the dumb alumni stuff and just go to Deep Ellum. Pretty cool neighborhood with breweries, bars, good food, etc. Of course, it's also worth remembering that Dallas is home to a Medieval Times...