Sitecore regular provides new releases for Sitecore Commerce and Upgrade Guides. As far as I can see, if you need to upgrade XC 9 Initial Release to the latest version, you need to upgrade Commerce Engine and Sitecore from version to version.

You can't skip migration to Update-2 (for example), if you want to migrate to Update-3. Of course, it will take a lot of time for upgrade environments and will affect project budget.

I think, that instead of upgrade better to choose another way and setup latest version from scratch and migrate content. Because only part which you need to take care - it's a content migration. After that you can just switch production to new servers.

My question is:

What is a good way to upgrade Sitecore Commerce to latest version, on your opinion?