Since a little while, you can vote for and suggest, what could be next for tchncs.de – use this thread to discuss suggestions or just use the Nextcloud poll in the link. :)
Most services will be tried without full commitment within the first while, because it is often unclear how well they scale, can be moderated or will be used. However i am not good at not continuing things... need to improve on that front.
What you can do here
Find the missing link, but also discuss certain software before voting or maybe for giving your vote (or submission) more weight – or just use it as a forum to find cool stuff.
I just tried Vikunja and I totally loved it! Years ago I was searching for something open and that feels lightweight which includes support for gantt charts. Vikunja checks all boxes!