I lived in Vegas for 5 years and go back every year to visit friends and you have many choices. First thing are you getting a rental car? If yes, then stay at the M over the Tropicana. Since you will already have been a Ceasars, going to the Trop will seem like a motel 6. However the M which is beautiful is way off the strip. If you rent a car be aware that many casinos now make you pay for parking and valet at most are not free either, even when you are staying at the hotel, unless you have a Total Rewards card at the Platinum, Diamond and Seven Stars levels.
https://www.caesars.com/parking
Las Vegas really has everything, just depends upon what you like. If it is hiking head over to red rock canyon.
https://www.blm.gov/nv/st/en/fo/lvfo/blm_programs/blm_special_areas/red_rock_nca.html
or the Valley of Fire
http://parks.nv.gov/parks/valley-of-fire
The Mob Museum is really cool and has a bar at every level.
http://themobmuseum.org/
A pp mentioned the Atomic museum, which is really cool, but if you are a US citizen and you have to book in advance as they do a security screening you can actually take a tour of the test sight in the Yucca Flats.
http://chemistry.about.com/od/nuclearchemistry/a/How-To-Visit-The-Nevada-Test-Site.htm
I would skip Pawn Stars, unless you are really into the show and want to possibly meet one of the "stars". Otherwise it is just a pawn shop and a mediocre one at that. They did buy the space next to them and put up a container strip mall. But by far the best container mall is downtown at:
http://downtowncontainerpark.com/ Not only does it have cool shops and a great vibe, they often have bands playing on their stage and some great food places.
a pp mentioned
serendipity, but it has closed!!!! But if you walk across the street and down to the High Roller in between the LINQ and Flamingo, there is a Sprinkles cupcake and even better in my opinion a Ghirardelli Chocolate store.
Or if you want the best milkshakes ever, and they also have alcoholic ones as well go to LVB in the Mirage. Disclaimer they were named BLT and got closed by the health department last year, but have now reopened to a A rating by the health department. I just went for a milkshake and did not try the food, but they have an open kitchen and we sat at the bar looking at the cooks and it seems they have cleaned up their act.
A must do is to go see a Cirque show, all of them are AMAZING, my favorite used to be Ka, but is now Michael Jackson's One. Just a note: Zumanity is a heavy R rating, no kiddos and no adults who are squeamish about human sexuality in all of its glory. It celebrates love of all by all, with a mock orgy scene. It is all tastefully done and very artsy, but it is not for everyone.
All of the headliner performers are wonderful....Just saw Britney Spears last month and she really put on a great show, even though I am not a huge fan, I still knew at least half of the songs she played.
Too hot on the strip want to take a drive somewhere cooler, head to Mt. Charleston.
http://www.gomtcharleston.com/ about 45 minutes from the strip.
Have fun!!!!