I'm curious what the breakdown of donations is. I only have 1 contact with a $10/month and 1 with a $5/month badge. Of course there could be others not displaying the badge. Signal really needs 500,000 people giving $20/month and plus the rich guys giving some millions on top of that to be in a safe financial position.
Maybe something that could be done to encourage donations is have the client estimate how much raw infra costs your usage created and display in the donation screen.
Communick is not "a chat program". Communick is a service provider, which promotes and works only with truly open protocols. There is no custom client or lock-in based feature that I have. This means that if you are my customer and you want to move out you are absolutely free to get your things and move to a different place instantly.