Honestly I could see it having HUGE potential if done correctly and could unlock nifty little items... examples below
Player A on social media issues an order for his/her soldiers to perform task x
-- Players in game would see a prompt for a time limited side quest. If successful Player A gets leader points + whatever rewards & in game players get standard experience points
Player A on social media issues a research & development order to unlock weapons to protect X
-- In game engineers follow the side quest and if successful unlocks weapons/tools/etc account wide for their characters and social side of things.
Player A starts building a starbase/colony/etc in social environments
-- Player A joins the game via purchased ME:X and performs missions with friends to speed up production or to get a first person view of the work in progress
Player B issues a command to attack Player A to pillage resources
-- Players would be able to select the Attack or Defend teams with rewards based on the outcome.
Player A goes to bed/vacation/etc
-- All friends of Player A would see their base & all orders would continue on unless already completed.
I'd say though, players who purchase the game & get to mission X should get a major starting boost over those on social network doing the F2P/Pay to win experience only. -- The only time I would like to see it modify in game experiences outside of say normal stat boosts would be on your 2nd+ play through instead of founding the colony/starbase/planet/etc again & starting from the ground up, you would find it as you left off previously and pick up from there.