Just saw 
@aggroed's stats show, where he discussed some of the ways the combat system will work.
I noticed he mentioned there wasn't a great deal of chance built into the game as it stands, so I have a suggestion.
When a player chooses a card, they also choose a temperament (for the whole match).
This means there are 16 ways to configure their 4 cards, and adds some chance to the outcome.
I'm not glued to the percentages or names; just throwing it out there as a suggestion.
Let us know what you think, in the comments.
As always, have a great day