I think it has been said that the second expansion is already in the works, as for the third...let get thru two before worrying about 3

I agree, i never play these types of games online because i just hate how EVERYONE plays on max max ultraspeed. It ruins the feel of these games. Not rts games, but yeah, empire builder games.
Actually i dislike RTS games online too, because its the same thing, everyone plays at max ultraspeed, making the sessions last 8 minutes MAX. Its boring..

I love long sessions, hours of fighting. This is also why i dont play Sword of The Stars online either. I would love to, but i love *more* to take as long as i want, play at my own pace.
So a diplomacy expansion would be amazing. Hopefully ending those annoying mission requests once and for all. Getting 11 missions in the first 15 minutes from empires youve never met is annoying, that icon flashes all the time 

^ or my money back?

must. have. more. info.

"[It's a] complete and utter overhaul of the diplomacy system," said Ironclad co-found Blair Fraser. "We are taking out the trash, burying it, digging it up again seven days later, cremating it and then shipping the dust to the dark side of the moon for an alien funeral."

Rofl...Sounds like the Hitchiker's guide to the galaxy...on the vogons

"The second micro expansion is really about both diplomacy and the non-military aspects of the game which will bring it more in line with the RT4X sub-genre we've labeled it as. Certainly, multiple paths to victory, especially non military paths, are part of that," Fraser said, adding that the introduction of additional game modes that will make the game more multiplayer-friendly is also a distinct possibility, pointing to the user-made Sins of a Solar EmpireDOME mod as an example.

WOOT WOOT... Can't wait for king of the hill, capture the flag, and of course survival mode, plus econ win

Your average online Sins game takes about 1.5 hours and many go for 2 hours with some lasting longer (and possibly much longer)--and that's with "Fast" everything.  How long do you think it should take to play a Sins game online?

Also...the players have voted with their feet.  They could choose to set the speeds to Slow or Normal if they wanted to, but invariably they choose the Fast speed and some people would like a speed that's even slightly faster.  I suspect that the overwhelming majority of online players would argue that slower speeds would make the game very boring and that playing against the AI is boring.

Come give online Sins a try.  If you want to play an RTS that takes longer than 8 minutes or 25 minutes...this is it!  If you can accept that as a new player you'll get beaten down while you learn the game and if you commit youself to learning to be a competitive player you might really enjoy it.