There are a handful of missing messaging features that are becoming increasingly urgent for us, and I think the discourse team probably agree they need to happen but they are lower on your priority list than ours. Is there anything I can do to help speed it up, besides becoming a hosting customer? 
These are the most pressing ones:
Well, if it helps @tobiaseigen’s case, #1 would certainly be appreciated over at Stonehearth.
FYI - #1 has now been implemented. Groups can be invited and removed from private messages.. 
… but #3 has not happened. It’s back on my radar though so maybe I will try to make it happen.
Regarding
I’d also like to keep in mind
For now, in my community, I am changing the email button text from “Read Message” to “View Recipients”.
I feel like pushing users to the site should be the main objective while trying to avoid the pitfalls.
I posted some email footer enhancements tips for Reply Privately and other features using existing Discourse shortcodes and Customize Text. I didn’t check any of the group email templates or related email text but maybe some of the codes are already present or could be implemented in a similar way.
