Your the boss, but why does Sins ( and other games )commit so many resources to MP game play, when it is >5% of your customers at best?
I can't speak for the developers, but people who enjoy online multiplayer are often a game's biggest source of word-of-mouth advertising. They'll have enthusiasm for it and encourage their friends to get the game. Perhaps it didn't work that way for Sins, but online multiplayer has proven valuable for other games, including other RTS games. It's certainly important for first person shooters. How would Starcraft have done without online multiplayer? People that play human opponents might also play a game long term, getting involved in clan activity and leagues, continuing to advertise the game by word of mouth whereas people who became bored with the strategically-challenged AI might have long since moved on to other games. A vibrant online multiplayer community also encourages the creation and dissemination of custom content. Overall, it offers much more potential value to a gamer than being limited to single player. You can finish a single player campaign in a couple days, but online multiplayer can hold a gamer's interest for years.
For example, there are still people out there playing the original Starcraft, the original Unreal Tournament, and even Tribes and Tribes 2. Those games are legendary in their minds. If sequels are made you can bet that they will promote them.
WBino, what do you think could be improved about the single player aspect of the game other than having a campaign? How do you think an investment of time and effort in online multiplayer detrimentally affected the single player game?
If you say, "I wish the AI were smarter", then the answer is to simply play against other people in online multiplayer; that's what it's there for, to offer opponents that are more challenging than the AI. If you want more planet types, more maps, and more ships, custom content is available. (I don't think the Sins AI is bad as far as AI goes, but it's just AI and will thus always be limited in its strategic capabilities.)