You folks aren't the first two to discover that the groups UI is (ahem) incomplete.  I've heard such rumblings from others, though I personally haven't built anything other than simple test sites with OpenACS 4 thus far (I've built plenty of 3.x sites, and my colleague Janine Sisk of Furfly's deployed two commerical acs 4.x sites - check out nybooks.com).

Any improvements to the UI will be welcome, that's for sure ... you might want to start a thread in the 4.x design forum describing exactly what you intend to provide.  That way others can chime in with whatever additions or changes might be needed based on their experience.

Even if you don't have time to accomodate other people's ideas, having the discussion up-front might be useful.