Again, your best option is to simply let everyone else use the class and unit type they want and avoid this topic altogether.
Most Rulers/Generals/Marshals who fail to heed the above advice do so with nothing but good intentions in an effort to get a win for the team. However, to quote the Inalienable Rights page again, "Some of the worst events of both human history and in BattleMaster were done by people with good intentions."
To quote it further:
"The basic rule is: Just shut up and stay 100 feet away from any and all inalienable rights, no matter how well-meaning you are."
The fact that we are having this discussion suggests that people are losing sight of this basic truism. If you are about to write a letter and you find yourself wondering if it comes too close to violating an IR, then for the love of Pete, do not send it. If it comes close, then it comes too close. Period.