So what card that "never goes" is best to fill Tomax's amazing ability slot?

Adrenalin Rush? Cool Hand? Lightning Reflexes?

Crack Shot.

Crack Shot.

For offensive, ordnance-carrying Bren.

Cool Hand for Officers-Shuttling Bren.

Lightning Reflexes for Mara Jade/Rebel Captive/Tactician-Shuttling Bren.

Adrenaline Rush isn't bed, either, for ordnance.

Crack Shot/ordnance.

All other options are paying way too much to get mediocre results at best.