Would need a little more info in the question to answer it properly, Myrrlyns answer is the first instinct that comes to mind.
I'm new to playing organised airsoft, but it would seem to me that without the emphasis being on an airsoft battle, newer players such as myself might be leery to venture out.
Based on your additional info however, it seems like you would be providing costumed extras. These would probably be great for things like VIPs or special interest third parties, but it would seem that the main op-fors should be airsofters, the core of the reason most people play. Anything extra should be considered for what it adds to the FUN of the game for everyone. What would be your rationale for adding these actors?