Well a couple of thoughts. One, the stock skid is a very capable skid. If you have the assualt, you already have REALLY good shocks, and if you have the Pro, you have pretty good shocks. Either way, they can be revalved, for your weight and riding style and give you a very good riding suspension. If you want to go a bit further than that, Carl's Cycles sells an upgraded shock package, that they custom valve, and will give you a Fox Float 2 and a Fox Zero Pro for the skid, that gives you a Very Very good riding skid.
If you are going to be running higher HP, (turbo, big bore, etc) I know for a fact, that the Timbersled Skid handles awesome, and will really help keep your skis down when you need it to. I haven't rode one, but I have also heard good things about the K-Mod skid for the pro.