Yep, I think Vilnius could work for me.
From the original suggestion of a day trip to Kernave and Trakai, it would probably need a private transport arrangement, but that is something we could sort out once we get numbers. I know the bus route to the Struve Geodetic measuring post, as long as people don't mind a 3km walk at the end of it :) (though perhaps that could be factored in if we get private transport)
Additionally, I visited a Drum and Bass Roller-Disco
in Vilnius which I guess would be the ideal night spot for an evening, I'm sure Solivagant for one will be up for that :)