The other key to a walk cycle would be the walk path. This is what allows your character to move from the spot they begin in, and automatically makes your character walk across the space. How long is a pace? It depends on how long you make your path, and how many paces you want her to take along it (the number of times the cycle is repeated). Of course, it'll look strange to have your figure goose-stepping across the space, but only moving in tiny increments with each step - you have to work out this relationsihp for yourself. But so far as I can tell, there is no 'standard' step.