The only thing that cannot be changed is the 32 holes. (Yes, technically one could transfer the guts to a 36 hole hub shell and then lace on a new rim. If it does not have DT or similar, high quality double-butted spokes could help. But given 32 holes, which is marginal at your weight, the best predictor of longevity is proper initial tensioning of the wheel. The front should not be a problem at all - it's the rear about which you need to be concerned.