I think having a tag for something like this would be quite reasonable. However, I have a couple reservations with your proposal.
First, in my opinion "arithmetic logic" is not an ideal tag ...
I realize that I am coming late to this discussion, but I am not happy with the tag situation regarding models of PA.
Currently I feel there is no suitable tag for questions about models of PA. This ...
I have created the tag synonym peano-arithmetic -> theories-of-arithmetic.
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