Not at this time... and perhaps not ever. Unless you have more than 5 drives, you should be able to use 5 triggers or less. Also, you have 5 per network, which should be enough.
About multiple triggers:
* Users don't like having to check a lot of different triggers.
* Users prefer to see directories for each kind of file (pictures, music, etc) rather than triggers for them.
* Too many triggers will make your ad too long.
It's always best to just organize your files into one folder with subfolders that tell what each kind of file is and let users stick to a single trigger, or only a couple (if you have multiple drives).
The only time it might be necessary for more triggers is if you're serving in 5+ channels on the same network... if that's the case, you really should limit the number of channels you're serving in. You're just slowing everyone's files down that way.