Building a smaller still

[TwoSheds]

Hi all, need some help on still design.

I've ordered a Brewhaus 15 gal/3" CM still but it ain't getting here quickly. This was to be my first still, but...

From all the reading/learning/watching I've done while I wait for the still to come I'm now thinking that a second, smaller still would be nice to have for recipe development and small batch spirit runs. That leads me to look at building something capable of doing spirit runs for batches (rum and whisky) between 5 and 13 gallons, and down the road smaller gin infusions and essential oil extractions.

So here's the questions:

Is 3 gallons a workable size for these needs? Based on my rough calculations I should be able to strip a 5 gallon ferment in 2 runs then do a single spirit run.

Is 3 gallons a good compliment to a 15 gallon setup or should I be looking for a 5 gallon boiler? I'm looking at the 3 gallon milk can from Mile Hi but open to suggestions.

What's a good heat source and controller for this size? My stove is electric and I know the on/off cycling is probably not good.

In this size I figure I should stay in a 2" column, right? If I go to 3" I'd need to go taller and might even need more power to push it. (If it didn't matter, I'd go 3" so everything would be interchangeable with the bigger one when it arrives, but I don't think that's the case.)

I'm thinking tri-clamp to make it modular and build my own Liebig with copper. There are more questions and details to work out, but I figure I'll start with this.

Thanks for reading and any responses, and for all the other info folks have posted here! Some great stuff!