Help me break my OCD analysis paralysis RE: thumper sizing

[Stags]

Hey folks. Hoping yall can help me break my personal analysis paralysis. Fundamental question- to add a 15 gallon or a 10 gallon thumper? Sitch is below:

I currently have a 10 gallon pot, 5 gallon thump, and 3 gallon worm. All powered by 2x 2kw elements. All copper. She worked really nice for UJSSM and sugar washes.

Recently got a new job and more $ so I figured I’d splurge on some new materials and equipment. I’ve also gotten proficient at all grain mashes but I absolutely hate filtering and wringing the grains.

My thoughts have centered around building a new 15 gallon primary and either a 15 or 10 gallon thumper to feed into my existing 5 gallon thumper and 3 gallon worm. So 15/15/5/3 or 15/10/5/3

My intention would be to strip with water in the primary and unfiltered mash in the big thump. Spirit runs through grain in the big thump as well, primary charged with low wines. Added benefit is that the primary and elements would only ever see clear low wines and water, so less cleaning burden/ longer life for that equipment. I’ve done enough math to conclude that I can achieve my objective of bold full flavored and bodied whiskey in either setup depending on how I charge and run her.

Thoughts on 15:
+More mash per run/ fewer strips
+Lower abv on spirit run from more 5% mash in system
-longer run times/ less control
-higher likelihood of dry elements

Thoughts on 10:
- more stripping runs required
+ more refined product from lower grain charge in spirit run
+better controllability due to smaller size relative to power input/ shorter run time
+lower risk of dry elements

On a purely objective basis, I think the 15 gallon thump has a slight edge just due to volume. That said my brain loves the idea of 15/10/5/3 because my brain loves the pattern in the numbers. 15/15/5/3 turns my math brain off. So I put it to the masters: 15 or 10?