I'm surprised that Trace isn't getting more love; IMO it is the pinnacle of a risky ability, as its usefulness is totally dependent upon teambuilding and prediction. For example, you could try to switch CAP4 into Toxicroak to get Dry Skin, but end up with Poison Touch if your opponent uses it as a lure (or something completely different if your opponent switches). Actually, many weather-related strategies and abilities follow a similar risk/reward paradigm when viewed with regard to Trace (think Swift Swim, Chlorophyll, etc), which would give CAP4 a niche in the weather-dominated metagame: it has the potential to adapt to any of them. Trace would also give CAP4 a reason to switch into Scizor or Genesect (to get Technician or Download) and risk getting KO'd, furthering the idea that every switch has to count.
Other than that, I'm liking Moxie, Hustle, and Weak Armor for this CAP. I'm neutral on Illusion, but don't think that Tinted Lens, No Guard, or Magic Bounce really carry any risk.
You've got to lose to know how to win.