The intended use is for a small association with some tenths of members - not for business. So i expect not much traffic go to the DC. But i may be wrong.
To what i've read here the quintessence is not to continue this idea due to memory exhaustion and the duration of the flash memory.
So instead i could go for a small box in the Intel NUC class. Getting a nice management WEB-GUI would be a bonus. Mostly on Users/Groups management.
I found a lot of guides for managing samba via command line, but GUIs seems to be very rare.
Paying several hundred euros for a MS Server license is not an option for us.
Thanks for contributing and giving some insights.