share back to the community.... a basic principle

[smbantjes]

Write more explicitly in the beginning of the text (features).
As a basic principle: a fundamental truth or proposition that serves as the foundation for a system of belief or behaviour or for a chain of reasoning.

That all you do on the software you will share back to the community.
(Included your templates). So that the whole community can also benefit and progress.

[mfrasca]

what you state above is indeed a consequence of accepting the GPL, and we have to formulate it in a way that makes it attractive rather than scary to the users.
the GPL, according to this nice article “why freedom matters” can be seen as a statement, that all of us adopting Ghini "can be trusted to participate in the community without holding something back for themselves".