My impression is that you'll need to play with resistor and/or capa values until you like what you hear. Theory is one thing, reality is another.
Tune it with an external circuit where you can easily subsitute values previously to soldering anything.
You could maybe use a 50-100K pot for the resistor and sub capas in and out until it's OK.
This "breadboard" would also be useful for checking how many stages you need : I'm not sure you'll hear much difference (if any) between 6dB/oct vs 12-18dB/oct.
Keep the corner freq formulae in mind so you keep things in the right ball park.
Alas I have no knowledge regarding latency due to cap values ...