I made some test but if you want a human face we must renounce to double F. The double F inevitably leads to a muzzle of an animal, belive me. So tell me if you want to give up it and have a human angry face. In my opinion the actual sign of #58 is very memorable 'cause it's simple (think to the Nike's icon). If we abandon this road for a human face will be less impact. But I rest at your disposal, let me know your opinion please.