It really depends on what you want.
Some things you might want to consider:
Are there some games/rules you want to enjoy?
For example, I prefer casinos which
o have Pai Gow poker, preferably the "face up" variation
o have favorable blackjack rules, paying 3:2 for blackjack, has the dealer stand on soft 17, allow doubling down on any two card hands, etc.
Are there any free-bees or discounts you want being offered, such as free gifts, free entertainment, free meals, free play, etc.?
Are there an adequate number of tables and slot machines that allow lower bet levels?
If you want to play table games, are the dealers friendly/helpful?
If you have been to that casino before, did you have a good time?