Are there any other strategies for maximizing my cash-on-cash return aside from going for commercial loans (with variable interest rates) or doing creative financing options (such as subject-2 or owner financing)?

Once they say yes then I discuss owner financing and how to will help their investment strategies. 

Look up BRRRR strategy

Yes, cap rates are compressing but even at mid 5s to 6s, w/a value add strategy, comps below competitors in price / rents and realistic underwriting that expects caps to rise slightly w/increase in interest rates, you can still make a very good return.  

Thoughts on this strategy?  

There are calculators here to help modeling, but you need a strategy first. 

I've spent the past few months trying to understand the numbers, develop growth strategies, and learn the basics of being a successful landlord.

I need some experience with this so I recently started developing a strategy to find my first deal.  

We financed this home at 80% LTV through a local bank (here is where I would have saved my capital and gone with FHA or another low money down strategy had I had the foresight, but alas, "it is what it is" as they say).My plan is to eventually use 1031 to trade up to 8+ unit buildings, then parlay that into either apartments, mixed use, or commercial down the line.Going forward: House hacking the duplex is clearly not the ideal situation with a toddler and a newborn.

I do understand how that's rather desirable, giving you better cashflow, an exit strategy, etc.