Kids might not notice how delicious the pizza is at a party, but the adults along can definitely tell. The pizzas should not taste like frozen cardboard pizzas, because even kids might take notice of that. It is nice if the restaurant offers other foods like salads, breadsticks, and pastas to supplement. It is also nice if the restaurant has alternatives for those with gluten allergies.
The games are probably one of the main things the kids at the party will look forward to. They of course will be excited about the pizza, but if a party place offers a lot of games and prizes for winning the games, kids will love it and so will the parents because the kids will be happy. Some places might charge for the games individually or give you a certain number of tokens to split between the kids. Then the kids will be able to turn in their winning tickets for various prizes.
The staff of the pizza place is also important. They should definitely be happy, cheerful people that are good around children, but they should also have had background checks so that parents will not have to be too concerned about letting their kids play on their own. The staff should never be rude or intentionally scare a child.
Security is an important issue with these kid's party locations. Some may have a check-in so that no child gets separated from their family or even kidnapped. This is something that you will definitely want to check out.
The entertainment at a party place like this is also important. You probably will mainly watch the entertainment while you eat lunch, but it should definitely be something that the kids would enjoy even if the adults in the group find it corny or annoying. It should really be geared for the kids anyway.
In order to really know if a place will be a good location for a pizza party for your kids, you will definitely want to go without your kids and check the place out. Make sure to taste the food and watch the entertainment. Go in the game area and see that it's orderly and not chaotic and that the staff seems to be friendly to the kids. You could also talk to the management about whether they do background checks on the workers.
After you check everything out, hopefully you will know which place is best for your kid's birthday party. They will probably love what you choose, and you will know that you made an informed choice.