IMO one of the cool things about Wallet is the notification that appears on the homescreen when you're in proximity of the venue or time of the event and automatically displays the pass when tapped. I wonder if "create your own" will be able to do that (I'm not sure how it would)?
I use Pass2U Wallet and set a location, if I end up at near Children's Museum or Community Center, my ID is ready.
Just enter the location and time in question as part of creating the pass?
I'm a fan of Wallet Creator (https://apps.apple.com/us/app/wallet-creator/id1486573384)
Zero dollars, lets you geofence passes when you create them.
That one's real fun if you happen to be near the train station a lot, and have an anytime return ticket.