"If we control too strictly"

...since you've never had any real controls in place, ANYTHING is going to seem strict to you ...

If a guest posting a request for some song doesn't even have the common courtesy to join and then post (since it is free) then you have zero obligation to provide ANY guest with ANY privileges ... Doesn't have to be 'trick or treat' 365 days a year. The MEMBERS here should ALWAYS take precedence over guests.

Hey I like my neighbours but I still keep my door closed so that they and any other strangers who happen to be passing by, can't just walk into my house anytime they feel like it and spray paint graffiti all over my walls.

And no I wouldn't prohibit the posting of song lyrics pertaining to polticial or religious topics. I would just very tightly control the ensuing discussions of such to make sure every one is nice and civil because the history of this and other unmoderated forums has proven time and time again, that SOME people are incapable of policing themselves. THAT'S WHY THERE ARE RULES, in all societies. :-)
People NEED to be governed.

I would however prohibit the blantant discussions of politics and religion when IT DOESN'T HAVE ANYTHING TO DO WITH FOLK MUSIC.

I'm outta here and am chasing my tail now.