What cards, if any, should I use for unimportant battles?

When the outcome of a fight is pre-ordained, or it's otherwise unimportant, I'd like to skip choosing battle cards. Are there a set of decent cards to which I should default? Or will the AI learn that I favor certain cards, and start to pick countering cards? If so, am I better off leaving them blank or just picking random cards?

Solution 1:

I usually use Barrier, so that any damage is absorbed by the barrier and not by my ships. Ending with Nano-Repair Systems can heal any damage that snuck through.

Using Nano-Repair Systems the whole time would not be unreasonable, but it does reduce your weapons' damage.