My concern for the OP using the word veto for something that is more commonly seen as a boundary issue is more directed towards the possible partners he will attract.
Veto is kind of old school now I think and is used as a distasteful word for "ultimatum." Its come a full turn since three years ago even. As have many terms commonly used in poly. I don't see a problem with using it if there is an explanation behind it, but frankly, if someone I was dating said he had a veto agreement with his wife I would not hear beyond that and quite easily assume the rigid version of the common meaning at this point in time.
I would assume that if I don't behave I will be told to leave regardless of my feelings, investment and time. I'd be one foot out the door already. I would hate to see that happen for the OP simply because he uses the word "veto" when to me (and generally others too) he is talking about his wife's perfectly normal and reasonable boundaries.
Really though, its up to you OP. Just trying to educate here. Take want you want and leave the rest.
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