The arena itself "looks good", but there are some flaws for sure. Here are my thoughts:
1. The seats are tiny. There is no leg room and you'll basically end up rubbing elbows with the person next you.
2. The food isn't that great, but very expensive as mixed drinks are about $13 and beers around $10...popcorn and hot dogs were movie theater priced +
3. If you in any upper level do NOT WEAR HEELS because the stairs are so narrow and steep if you so much as trip you're likely to fall all the way down. It's bad. I looked down from the top and got vertigo and the workers just tell you to move slowly and "hang on top the rails". I understand wanting to pack that place full of seats, but come on....
4. When you exit from the top they don't have enough escalators so you're usually stuck waiting for a bit unless you want to walk down a few flights of stairs.
5. The "Park" area in front of the arena is great. Lots of new restaurants and places to grab a drink
6. If you have t-Mobile there are places to charge your phone for free in the arena
7. Quite a few concessions stands
8. Parking is $10 if you pay ion advance online or $20 day of. I parked at the Excalibur and walked over (not bad) and it was free with your Nevada idea. yay for free parking.
The concert was great. I don't think Coldplay could play a bad show if they tried, but the venue is eh. I'd suggest getting either floor or the level right behind (sections 1-20 ish?) for the best view and to avoid the death stairs. I was in section 204 row H and the view wasn't horrible, but I'd definitely like to be closer next time.