"because i need to be able to switch them ON|OFF at will."
Instead of enabling/disabling the #groups, you could set or unset %sx2.XXXXXXnote. (You only need to "/set %sx2.XXXXXXnote 1" for the condition to be true)
Code:
on *:NOTICE:*:*:{
  if ($nick == sexgod) && ([color:blue]%sx2.sexgodnote[/color]) { sx2echo 14,00 $+ $sx2.kbig($nick) $sx2.sgod($1-) }
  if ($nick == nickserv) && ([color:blue]%sx2.nicksvnote[/color]) { sx2echo 14,0 $+ $sx2.nksv($nick) $sx2.nksv($1-) }
  if ($nick == memoserv) && ([color:blue]%sx2.memosvnote[/color]) { sx2echo 14,0 $+ $sx2.cham($nick) $sx2.cham($1-) }
}