Hello Kevin Bouwman,
Thanks for reaching out to the Microsoft Community.
Based on your query, I understand that you're interested in adding additional templates to Microsoft Teams for Education when creating a new team. According to the official documentation: Choose a team type to collaborate in Microsoft Teams, you can only choose from four predefined team types.
At this time, adding or creating additional custom templates is not supported. This design choice ensures a consistent and standardized experience across educational institutions. However, you can still customize each team after creation by adding channels, tabs, and adjusting settings to suit your needs.
I do understand your concerns but since it's related Microsoft 365 product services and features option under product design, I believe that the related product team can develop some convenient configuration based on customer requests.
Therefore, Microsoft recommend submitting feedback by going in Ideas · Community (microsoft.com)
Please note that the community team and the Microsoft product development team are separate entities. For suggestions regarding features or design queries, users should submit their feedback directly to the Microsoft product design team. Once submitted, your feedback will be forwarded to Microsoft and routed to the appropriate product team for review and consideration in future development across different OS devices.
To see more details on how to submit feedback, see this article Learn about how to provide feedback to Microsoft - Microsoft 365 admin | Microsoft Learn.
I hope I have provided you with all the required process information for this current scenario. If you need any further information from our side, please feel free to do so.
I would really appreciate your precious time. Thank you again for your kind cooperation.