This is going to seriously depend on her confidence level.
1. Is she self concious about her body?
2. Has there ever been anything in her past that this type of play may trigger a bad feeling or uneasy feeling?
3. How secure are you both in your relationship?
I think that this sort of thing CAN (not always though) invite a lot of negativity into a relationship IF you're not secure with each other, your relationship or yourselves. If there has been ANY issue in the past, I would definitely leave it alone until it comes up in convo. Maybe try to sway the convo towards trying something like this, but don't suggest it.
Also, do you have anyone in particular in mind? If so, how comfortable is she with these people? Will she feel as though you like so-n-so better or maybe that you have underlying feelings for this person?
This is something that needs to be handled delicately, depending on your wife and your relationship.