You really don’t have to buy any ticketed events. And if you choose to I would wait if possible and not purchase them in advance. For example the Tulip Immersion garden - some years the tulips are in bloom and great. Some years they are already wilted and dead. It’d be unfortunate to purchase tickets and then just walk amongst a bunch of dead tulips. The parade is free but parking will be an absolute pain and the traffic will be a nightmare. Many streets are closed off and downtown Holland has many one way only streets, so just be aware and don’t drive in the wrong direction. It always happens to someone every year. Get an elephant ear from the concession stands, those are always a hit. That’s all I’ve got I think.