What to Watch Out for in Your Players

[Keltest]

Allow me to rephrase:

“As a general rule, unless there’s a specific reason not to, please play as your gender.”

Does that seem less strict? Because that’s basically what it is.

Not really. Either "a specific reason not to" includes "because you want to" in which case its a meaningless rule, or it doesn't, in which case youre still just locking people out of playing characters because you don't want to give them the chance to do so.