Must have been a different Circus Circus than the one I went to a few years back. Dirty, dank and depressing is how I found it.
Most of the casinos south of there are good but bring your money. If you must stay on the north side, stick to Fremont Street Experience downtown. Lot of low rent stuff there too but it's policed a lot better and well lit. It's also where you can get deep fried Twinkies and find slot machines that still take - and eject - real coins. Slot machines were a lot more fun when winning a jackpot meant you had to fill plastic buckets with quarters and lug them up to the cashier.
I was extremely disappointed to find winning meant getting some piece of paper rather than cash coins. My wife, who had been to Vegas a time before me, told me that it's been a while since winners got cash instead of a piece of paper to take somewhere and get cashed. How much more fun it must have been to win and actually get coins immediately.
I ended up just playing until I ran out of my allotted quota, ten dollars, and quit. I don't think the casinos were unhappy to see us leave town.
Gambling requires waiting for the right circumstances and then not gambling at all if the whole place looks dead to begin with.
Fremont Street experience is worth once seeing, but the whole place is like visiting an old bowling alley down their.