[trechriron]

One of my thoughts to make this "more fun":

Make up 10 characters (125 points, 50 disads). These are the "ZA newbs". They are randomly chosen at the start. The beginning would be intense, with a big BANG up front zombie encounter that would increase the chances of a PC death. If you die, you pick another character. Play for about an hour and see where things fall out.

Then...

Hit the pause button, fast forward say 6 months into the apocalypse. Hand out the "hardened survivor" characters (say 200 points, 75 points in disads). These new characters would have the "how I survived the ZA and all I got was this stupid T-Shirt" background blurbs. :-)

Continue the rest of the CON scenario.

It could give the initial horror punch in the setup, showcase character advancement, and provide an exhilarating survival romp to finish it out. I would share this setup before we begin to manage expectations and give the players room to "ham it up" in the first hour playing the ZA newbs without fear of the 4-hour slot being "ruined by a horrible death".