I have stayed in a Tower Suite and a standard room in the main original section of the hotel. I have been to their Sunday Las Vegas pool party called Rehab a few times over the last several years.
They have fun outside concerts by the pool, just be sure to show up early to try and grab a chair. There are other large events now that there are several pools for the new Tower Suites.
I have been to The Joint concert venue and it has one of the clearest and loud sound systems anywhere in Las Vegas. Many different kinds of events are held in The Joint, from roller skating to rock concerts.
With all of the upgrades to the new section of the Hard Rock, revamped dining options, new nightclub venues, this is why as a local, I visit often.