not much MP strategy talk in this particular forum. There is an MP forum here though that you could try.
rah brings up good point that it depends on what type of MP you are playing. I was never into MP and only messed around with it some years ago on the servers, and played a tiny bit of pitboss. Playing on the servers is riddled with trolls, kids and elitists..at least it was. I did not find it fun and as rah mention, guys will quit games fast.
Pitboss though is often a different animal if among friends. Usually there is a set of rules in place so that is something to keep in mind. Rules such as no tech trading (usually standard) and an enforced peace for set number of turns at the start. If that's the case, then some SP strategies are still beneficial and improving your SP skills is still a very good idea.
Anyway, I would check the MP forum out and see if you can find folks to discuss this with, and you might find some friendly games to join. No idea how active it is over there now.