This is the major airport in Las Vegas. Usually when I go here, I arrive 1-2 hours before my flight departs. One thing I like about this airport would be how clean it is. The bathrooms are very nice and the janitors work hard to keep them clean.
Security is not much of a hassle. During the weekends, more lines are open to accommodate the weekend flyers. Don't expect any more than one or two security lines to be open during weekdays!
The walk to the gates is not too horrible. I usually think of it as a scenic walk if my gate is at the end of the terminal. The flashing lights coming from the slot machines make it a little better as long as you don't waste your money on them!
There are a huge number of place to get a bite to eat. However, don't expect any stores to be open after midnight. Despite this, there are plenty of vending machines to satisfy whatever your needs may be while you wait for your flight.
There are also a bunch of charging stations that come in a variety of forms. Some are on tables, some are in booths, and some are on the sides of couches so you can charge and have a comfortable seat at the same time!
There is WiFi, but don't expect any good bandwidth. After all, there will be hundreds of other passengers using it as well. Good thing cell phone service is great here!