Is there a list somewhere of what templates are included?

The best place to see the list of things included in the better sheets ltd is at bettersheets.co/tools
This list includes templates and tools like the newsletter creator called "Better Letters" and Onlysheets, the paywall for google sheets, as well as Atomic Sheets (100 elements to add to your sheet)
the directory of bettersheets.co/templates includes 3rd party templates sold on other sites like etsy and gumroad (not made by Better Sheets)