I'm not sure exactly what constitutes a viable "chess alternative," but if you're open to going beyond two player and investigating other styles of games, check

I'm not sure exactly what constitutes a viable "chess alternative," but if you're open to going beyond two player and investigating other styles of games, check out the top games on BGG (boardgamegeek.com). Many of these have a great deal of strategic depth and subtlety: http://boardgamegeek.com/browse/boardgame http://boardgamegeek.com/browse/boardgame