Gnembon's Gold Farm platform shape to platform ratio

I want to maximize gold rates from this farm and came across [this](https://www.youtube.com/watch?v=4w7IW5Fh2zM) video by BKraker where this platform of 491 spawning spaces is ideal for improving rates over the initial 210 spawning spaces design by Gnembon. BKraker's design must require lesser platforms (original had 19), but how many?

In my calculations I am not able to determine the upper bound for pigmen lifetime that will eventually clog up the mobcap, any help in calculating the optimal number of platforms?

Could smaller platforms be added to improve gold rates further?