I think max human readable display rate is about four readings per second.
I would not want to see or use any pressure data older than 250ms if I would pick a 4Hz display rate.
So I would do any averaging/smoothing within that time frame, for a true/instant pressure, without lag.
Koepel is right about having to know a single pulsation duration.
Without that you can't choose the best averaging algorithm.
Leo..