OpenGL draws millions of triangles many times a second. I'd suggest that this is not a problem we need to keep solving :-)
However, doing that wastes CPU cycles that you can use for other fun stuff in the game. In particular, monster AI will easily soak up any cycles you want to throw at it, and the more you can, the more interesting your enemies will be.
AI code can easily eat any free cycles you want to give it: you can always crank up your pathfinding distance or the number of turns your AI looks ahead.
The problem space of a roguelike is massively larger than chess and that can certainly keep a supercomputer busy.