Super easy airport! Compared to ATL, this airport is HEAVEN! I never feel any anxiety when I know my layover is in Las Vegas. This airport is almost as easy as JAX. There are great places to eat for the fast food lover or the more health conscious ones.
If you want to try your luck gambling, there's plenty of slot machines ranging from penny slots to $1 slots and more. The gift shops are full of souvenirs that you forgot to get while you've been on vacation and there's plenty of snack places to grab and go. My personal favorite: Auntie Anne's Pretzels located in the Southwest terminal.
Overall, whenever I'm booking a flight out west, if McCarran International Airport is a layover option--I'll fly through there any day! Viva Las Vegas! :)