I think there are two main factors that affect game pace:
1. Familiarity with MeG. The more games you play, the faster you become. Familiarity with the armies (your own and your opponents) also helps.
2. The player themselves. Some players are just faster than others. I am already thinking about my next action as soon as I have completed my last action. Some of my slower opponents seem to "drift" whilst I am making a move and act almost surprised that I have finished an action and that it is their turn again. I have also noticed that certain players start slowly and only seem to speed up when they are close to winning.
There isn't ever going to be a magic bullet to solve slow play, but the scoring system encourages getting a result.
Finally, it is important to remember to have fun! I told an opponent recently that having good games was more important to me than getting a podium result (both is better!). He didn't believe me but I still maintain it is. This is certainly the case at Britcon where we play 6 games. I think I have chosen quite a good army, but I am pretty certain that it will give me six interesting games.
I also would like my opponent to enjoy the game (even when they lose!). If they don't, we would end up with nobody playing the game.
Richard