The best way to decrease your play time is to play aggro. The base aggro strategy in MW is big creatures. It is the fastest, easiest way to get the biggest board presence. Turn 2, you can reliably drop Adramelech, a pet Steelclaw, one of the legendary angels, etc and I can guarantee your games WILL be shorter and more fun.
I wrote an in-depth guide on aggro in the strategy section, and I would highly recommend using one of the openings I have listed there. They're at the top of the page, so you don't have to read the rest if you don't want to.