Here is a welcome join counter
on first join:
set join message to "&3&lWELCOME &b%player%&f has joined for the first time! &8(&7##%{joins}%&8)"
on join:
set join message to "&8[&a+&8] &b%player%&f has joined."
on quit:
set quit message to "&8[&c-&8] &b%player%&f has quit."