I get the appeal of a self-hosted tool, but my suggestion is to do the important ones in person.

When I ran a Linux group years ago, the decisions that mattered were settled around a table. For a big decision, the dialogue and the discussion that lead to a common agreement are the real work, and in my experience no software does that part for you.

For small stuff, a simple poll (or no poll at all) is fine: the core team decides and shares it as information. Save people’s attention for the decisions that need it.