The game needs a in-game chat system to communicate with other players especially with new players, because spacelords isn't very friendly to beginners. For example, I've seen many "baby" Harec in mission "No Reservations", killing all the Elite soldier with their rifle and end up lost the game (with/with out antag, or Mr. baby Harec is the one true antag). Losing game for such reason is annoying.
Therefore, I think we need a in-game chat system to improve the game experience.