I originally bought the 12 Pro, and called Apple today asking about my return window. Well, 3 hours later and I have the 12 Mini updating iOS...
This thing is small. Much lighter. And this is weird...but it just feels more like what an iPhone should feel like to me. My last iPhone was the 7 (I loved that phone) and then I took a sabbatical to the Note 9. The 12 Pro felt too large in the hand, a bit heavy and not that special. And between a 12.9" iPad Pro, a Mac Pro and a 12 Pro I have too many 'Pro' end devices and large screens to keep me distracted. I need to stay off my phone more, not consume more off of it. The mini makes that a bit easier.
I'm going to give it a few days before I return the Pro, but I have a feeling I'll be keeping the Mini. It just feels right.