an airline is an airline
they are all charging out the ass right now
they are all cutting back on luxuries
unless you are springing for first class or business class you are going to be cramped
pick the one that costs the least... would you rather have $200-$600 more in your pocket, or a slightly more comfortable seat for a few hours... me personally i'd take the cash (granted comfort does get more important the longer the flight is... anything over 5 hours, i start looking for more comfort) also several airlines will offer upgrades at the gate or at check in for $40-100 (well worth it considering booking the upgraded seat initially will cost you 400-1000 more)
check for flights out of smaller airports in the area, they are often less expensive
also check for flights on commuter airlines... they also are usually less expensive
flying on a tuesday or wednesday is always less expensive
jet-blue has flights from vegas to salt lake in the $70-90 price range each way for a tuesday to tuesday trip