Hi, a few notes, and questions...
Is your game turn based? Or is it real time? If you don't have realistic 3d sound, then using a grid is probably easier for players. Instead of frame rate, think about it like the update rate of your main loop. Before the player takes a step they are standing. When standing, speed is zero. When stepping, the person gets some acceleration and moves. Then they get some deceleration and stop. It's more complicated than that, but the more physically accurate you want it, then more complex your code will be. If you're more interested in making the game, than a physics engine, you might want to consider looking at one of the physics engines available. Keeping the game movement to grids might make it easier to play as well as program. cheers,
