Expert Shield Tech - 5 points
While defending, during the Spend Defense Tokens step, when you spend a (Redirect) defense token you may reduce the total damage from the attack by 1 instead of resolving that token's effect.
A quick note: The defender cannot spend more than one defense token of each type during an attack.
So if you take Expert Shield Tech, you can replace the redirect token effect, but you can't also spend another redirect token to get the standard effect. This is an either / or not an addition to the standard effect like Damage Control Officer is.
Still, this is a way for you to use your tokens to prevent damage, which is really good. It obviously works best on ships with multiple redirect defense tokens, as well as ships with multiple officer slots so that it doesn't take over a slot that is needed for something else. This will be most useful against small damage attacks, such as squadrons, or if you are taking damage to a ship with no shields left (and a considerable amount of hull remaining).
My personal thoughts for best ships are for Rebels:
MC30c - Dual redirect tokens, and no good way to reduce inbound damage especially against squadrons. Less random than Lando for keeping Admonition alive, and combines very well with Mon Mothma.
Starhawk w/ Unity - Dual redirect tokens, lots of hull, two officer slots.
MC80 Command / Assault w/ Early Warning Systems - Dual redirect tokens, chaff tokens can go on whatever shield zone is depleted and you can reduce damage on other, shielded zones.
Star Dreadnaught - SO MUCH HULL. Dual redirect tokens. Many officer slots. Expensive, so a 5 point officer doesn't feel like overkill.
Arquitens - Dual redirect tokens, can combine with either Early Warning Systems or Reinforced Blast Doors for extra hull.
Imperial Star Destroyers - Dual redirect tokens, some have access to Early Warning Systems and all have a lot of hull to chew through.
Victory Star Destroyer - Dual redirect tokens, decent hull, and not a lot of shields to chew through.