Your wife does have a hard and tight looking ass. If she works out like you say, she should have the endurance be able to handle at least 3 guys pounding her at once. For her to be a Hotwife, she has to have one cock in her mouth, one in her pussy and I would want to be doggy mounting her with my cock in her ass, all at the same time.
The most important part of this " Hotwife mini-gangbang initiation" is that each male unloads his cum into her. You can imagine the thrill of seeing your wife leaking cum out of all her holes, and none of it is yours.
She would now be considered beautiful fuckmeat for men.