If you can fit larger tires in, that would be one step to reduce stress on the wheel.
In addition (though I'm not sure what kind of spokes/pattern you currently have) you might want to look at something like a standard 36 spoke three cross pattern, possibly with Deep V rims (very tough, as far as I understand.)
I have Mavic T519 36/3x wheels for fatter tires on my touring bike, and Ultegra Open Pro/XTR Open Pro with 32 spoke 3 cross for skinny rubber that I'm just getting really broken in. No trouble with either yet, knock on wood.
FWIW I'm about 215-220, and ride with cracked roads/potholes etc. through Brooklyn. Your needs will change based on your conditions...