20/24 spoke count sounds like an invitation for trouble for a big rider. The Easton 30 is a good wheel set but maybe not strong enough. How about the Mavic Open Pro or for even less money the MA3? I think both are more than strong enough for we large riders.
It looks like you are running a MTB bike for cross. What wheel set is on your rig right now? Do you have plans for a cross bike? I am 6'1" and weight 225 and run stock wheels on my Gary Fisher Erwin cross bike.