You are 'forced to use an SC in MP'? Added to that is the obligatory 'if you want to be competative'. I still disagree, there are enough ways to master the SCs that I don't think I'll worry about them too much...
Of course some of it is the map size and the number of opponents. If the map is big enough so that you probably won't run into the SC early its easier to not use one, I've not found my expansion to be hampered when not using a SC anyway, usually the boost you get in research and earlier summons makes up for the conqurering abilities of the SC.
Also I don't see why you can't play a game with random opponents as it is. All you have to do is to randomize them yourself. Of course you'll still know who your up against from the start, but you'll be forced into playing against whatever nations are chosen. You could also ask a wife, roomate, child, ... to randomly pick the oppostion for you I suppose. Yes its a bit more cumbersome, but it is emminently doable
