Making the most of the cards you have and using them appropriately is a sign of the good player.
Having a plan and sticking to it is another sign.
Simply reacting to your opponents moves and abandoning your plan is giving the game to your opponent - just like in chess.

Generally I like to try and work on the assumption you'll be able to move three or four units before long in a section - and so I try and position myself so that can be best exploited. I tend to find attacks with two units rarely carries enough momentum and just turns into victory banners for your opponent.

Cards that allow for three or more units to move in one go turn up with enough frequency that I think you can wait for them.

I think I've decided to always hold First Strike till the end game - so often it is down to a banner or two each to victory, and this (especially against that isolated one block heavy infantry) is an excellent trap to steal a win.