You know, I've never used iTunes. So never tried backing up and restoring from it. Does an encrypted iTunes backup restore all settings? (including passwords, Wallet credit cards, health info, etc/) If so, I might try that next time.
I think under the 12.4 update, you can directly transfer apps/info from one iPhone to another. Though I don't know how to get the new iPhone to 12.4 to start that process.
I've used the restore from iCloud before several times. It seems to work pretty well, provided you have a decent fast WiFi connection. You do have to log into your app's once again. And you have to set up your Wallet credit cards again. But it seems to work without any major issues.