When are you here? We have an international Jazz Festival this week. Most of the downtown area has an event or two happening. The Red River EX is on about the first week of July or so. It has become a rather well done local fair. The Ponys run in town all summer. We have a real nice baseball park down town, The "Gold Eyes" play in an entertaining independant league. CFL football is just about to start. We have an large number of public golf courses.
Night life will depend on where you are staying. Out near the airport the restaurant of choice is "Grapes". There is a "Hooters" nearby as well although sadly it are not nearly as nice as USA ones I have been in.
Downtown has the "Forks" Which is an old railway yard re-done into a rather interesting tourist trap. There is an excellent river walk among other attractions there. The "Exchange District" is the closest thing we have to Night Life with many food, beverage and dancing establishments within a couple of blocks.
There are several museums and a zoo if you are so inclined.
Believe it or not, about an hour north of the city is a terrific beach. Rental car rates are livable.
We have just come through several weeks of heavy rain and the temps are now in the high 20's C. What that means is the MOSQUETOS are hungary and large enough to show up on radar. Dress accordingly.
We are no tourist heaven but not the armpit of the north either. Like all Layovers it will be what you make of it.