If being debt free is your goal (which I wouldn’t recommend because it diminishes your ROI), pay the 6.55% debt off first.

However, there gets to a point where we reach a diminishing returns effect; the more money we put in yields stagnant or even inverse results.

The places to park money diminish because there are fewer projects that demand that much capital and are willing to pay high rates for capital2.  

The increase in home prices will prevent new inventory from getting on the market due to diminishing returns.

Still solid, but the physical resources of land diminishing + population growing likely will yield better but significantly more work and risk.You're wanting to hit a grand slam on your first at base.

If you want the protection of an LLC (which is diminishing in its protection power), use a California LLC and pay the taxes and fees. 

The bank is a horrible place to have cash sitting idle as inflation diminishes its purchasing power.Deals can still be found if you look for them.

It may not be considered financeable; that diminishes your buying pull to investors or cash buyers willing to take on a project.

But page speed has a diminishing return as you get below 2.4 second load time when it comes to SEO and conversion. 

I also experienced a frustratingly high number of early payoffs that seriously diminish returns.