QUESTION???

What is a good rope length for an intermediate rider riding at 21-22 mph?

Depends on the boat but probably about 70' or 75' is about what it would be behind most.

A 06 Malibu VLX with full ballast and wedge employed with a 3 foot handle. Any new advice?

dude, rope length is diff. for everybody. This is not really a question that can be answered here, just keep messing around with it untill the lenght feels comfortable to YOU. The wake should be clean where your jumping and you should be landing on the downslope when you do tricks.

PS: you have a brand new Malibu VLX and you dont know what rope lenght??

70' should be a good starting point....once you can clear the wake comfortably toeside, then let the line out.....that is assuming you are working on clearing the wake from both sides. If you are just working on one wake jumps, riding switch, surface 180's, ollies then let the rope out to 75 or 80' as long as the wake stay's clean.

intermediate? you may not need full ballast either

only 21 or 22 mph? I would say 60-65 feet for a beginner. Depends on the boat.