Sorry for the delay!
I did an extensive poll around my friends
We decided that "Lentäkää vapaasti" does NOT sound stupid. The first friend didn't like it more for personal reasons. So, it's the way to go for Finland.
That would be the Finnish livery (Finnish Rajavartiolaitos "Border guarding service"):
Some more...
"Daddy, buy me a joystick!" - "Iskä, osta mul joikkari!" (Really colloquial kid language)
"Bombable" - "pommitettava"