As I have mentioned in another thread, there are several well-established scenarios that are particularly popular within this genre. I don't see 1v1 and 3v3 dueling being enough to retain a significant online audience. I really think that as a bare minimum they also need a base defense mode, a capture the flag mode, and space hockey. Space Hockey is probably the "most star control" of these, you could create a Star Control universe sport, you might even have it mentioned in adventure game or even have there be a quest related to it to introduce players to the "sport". They could do a lot with space hockey, and of course would want to give it a star controly name like FrumpleBall or something.
It's also kind of odd to be considering 1v1 and 3v3 dueling... 1v1 and 2v2 ("wingman duels") dueling have been popular in similar games, 3v3 has never really been a thing in these types of games. If the game is going to be successful as an online game just dueling isn't going to do it all by itself. Base Defense, Capture the Flag, and Space Hockey at a minimum really are needed to retain an online audience.
I would also do 3-sided 1v1 and 2v2 dueling because the three player dynamic works so well in this genre, and the Circle of Death scenario I mentioned in the other thread because it would work so well with Star Control, but these would be "extras". They aren't real;ly necessary.
You guy's should try out "Continuum" at www.getcontinuum.com. Death Star Battle is an excellent base defense zone, and they call hockey "powerball". In Subspace dueling was a niche type of thing that a minority of players took part in, generally only the very best players are into dueling. Trench Wars (base defense), Death Star Battle (a better base defense zone), and hockey are by far the most popular zones in Subspace and similar scenarios are the most popular in other similar games.
I really think that 1v1 and 3v3 dueling alone will only attract the hardcore Star Control fans to the online game and pretty much nobody else. With a full lineup of the favorites of this genre, this could wind up being very successful online.