You shouldn't really release your first add-on. They tend to have issues/room for improvement/sometimes aren't good enough. And most of these have already been made/don't need to be made.
/playerCount - was done badly and will only work on a non dedicated server. Instead of NPL_List.rowCount() you should do clientGroup.getCount()
/make - is pretty abusable, but I guess it'd be the host's fault for making dumb people super admins. Plus it doesn't work correctly for making super admins. Super admins have .isAdmin and .isSuperAdmin set to true.
/burn - will cause an error in the console if the target's player doesn't exist.
/datablock - Doesn't even exist. It's /make.
/make - If it does work, it also has the same problem as /burn.
/scale - Same issue as /burn.
/warn - The last argument in the command to the client isn't needed, as serverCmdConfirmMessage doesn't exist.
You also don't need to do %var @ " " @ %otherVar. SPC connects them with a space in-between. Like so: %var SPC %otherVar. Same thing. Just easier.
As you're new at making add-ons, you should ask someone to look through the code first. That way you can avoid many mistakes, get constructive criticism, and learn some new stuff.