Does FFG need to release a new counter to ions?
As of right now the best defense against ions is to run large based ships, or swam type lists of 5 or more ships. I would say defensive ships, but you don't want to have to save your focus for defense if you can help it - especially since most ships that can shoot ions are fairly tough.
But as for a new defense against ions? I'm not sure, but I really wouldn't mind. Perhaps a card that prevents ANY tokens from being placed on your ship? Or maybe a card that gives you a focus or evade any time you do a 1-speed maneuver? What do you think?