I can say, if you guys really do this you(husband) need to be prepared to see a side of you you've never imagined.Long-term for us, at least to start out.
We're newbies, and my Wife has only dated and slept with me, so She'll need the trust that's built over a long-term to feel safe and comfortable to explore Her sexual and submissive sides.
Maybe eventually She'll feel confident enough for one-night stands, but we know what will work for us for now.
We do this with a guy we know. My very normal wife gets five times more turned on than she ever did with me. We had a good sex life but since we started involving a 2nd guy she absolutely loves it. My wife does things now she wouldn't befor. Anal no problem with him or me.