The OP has been severely misled in thinking that saving 400 grams in a wheelset should be his next priority to go racing... at 210lbs.
The weight savings/body weight ratio with the wheels is 0.42%.
The most outright effective thing for him to do is stick with the wheels he's got and lose 40lbs off his body.
The weight savings/body weight ratio then would be 19%.
And would be a whole lot cheaper to achieve.