If I continue to run numbers and find this to be true across all potential house hack situations, what are your thoughts on me focusing on building a larger sum of capital to invest in a single-family, strictly rental unit?

Biggest difference is going to be the tradeoffs (which has pros and cons) of lower rates and fees but much more hassle, paperwork, time suck and potential for deals not working with strict requirements (conventional) vs. hard money (higher rates and fees, but much quicker, much less documentation and time and hassle, and a much lower likelihood of deal dying - hard money lenders can be much more flexible)

Check with a lawyer, but I don't think an HOA can regulate what you do INSIDE your house and beyond the screen door would be "inside" I would think. 

I would look into regulations first.

Probably wouldnt be an issue for the next few years but I agree with you if the city decides to tighten regulations via third party I might be opening a can of worms.

Having an attorney on your side that can explain the nuances, pros, and cons to the property owner while still insuring you can flip the contract is the challenge that I've come across in NY.Wholesaling in many instances is not in the seller's best interest especially if they have a strict deadline within which they NEED to close.

CPAs are licensed professionals who are highly regulated and are experts in tax filing, not necessarily 1031 exchanges, which is more of a real estate attorney function.

FHA is a strict loan product, and not always rehab friendly.

JC has strict rent control laws so you know...    

You're not likely to find a silent partner...first you could run afoul of security regulations but that's another issue.