I certainly expect kids who never started wargaming via board games with lots of numbered counters struggle to grasp computer wargames that continue the visual practice. And no matter how much some might like to think graphics don't matter if the gameplay is good enough... to a significant chunk of players, they do. No shiny 3-D effects, no deal. We are a dying breed. Unless, perhaps, you can make sort of cute, retro, 8-bit style. That seems to work at the moment. But then we do also live in a world where most top "strategy" games are largely dependent on furiously mashing the mouse button umpteen times a second with precise pixel pointer accuracy. Incidentally, was Hearts of Iron the game where the AI does bizarre things like Albania trying to launch seaborne invasions of Spain?