Suggestion: Enable friend to join a solo session.

It's really frustrating. This is supposed to be a game played with others / friends.
Why are you making it so hard for friends to join an ongoing solo session? I often find myself on a solo mission, when suddenly a friend comes online. So in order to play with him, he has to either wait for me to finish my voyage, or I have to quit the game, which means I lose my progress and my voyage. Why can't a friend join my session or why can't I invite a friend to my session without losing everything. Make it so He can join in and vote for the voyage on the table, so that he has all the maps too. This can't be that hard to implement,