Good to hear you say that Luke. The first thing I did when I got my F3HP was to swap out the Type K screen for a Type B screen (solid matte), which I prefer for focusing. Sounds like the Df screen should pretty much mimic the Type B, so if and when I can afford a Df, maybe I won't have to worry about changing out the focus screen.
I have the F3HP and compared the two when I rented the Df (I had one on order when they were first announced but rented one to be certain about it; but it turned out not to be the perfect fit for me personally. I wanted the D4 sensor but wasn't ready to give up my D3s for a new D4 at the time, either.) I found that the difference was that the F3HP screen is 'coarser' than the Df and not quite as bright. I could be wrong, but I think that might be part of what makes the older cameras a bit easier to manually focus.
I wonder if Nikon will continue with the Df and make another version. I hope so. But I think what's part of the issue with making a 'FM' style digital body are the current G lenses with no aperture ring. There will have to be a wheel or something to adjust the aperture and there's no way Nikon will make a camera that can't use their latest G lenses.
As an aside, when I am interested in a new photo product I try to rent first or borrow a demo from my vendor (another good reason to have a good relationship with a local retailer.) Invariably when one owns a camera or lens they will speak highly of it (why else would they still own it), and if they do not own then they will post the negative points that led to that decision. Wanting to feel good about what you own is just part of human nature, and dismissing something because it wasn't what they had hoped for is also normal; i.e.,
people take their personal preferences very personally. We rarely get unbiased views one way or another with these sorts of threads. It sometimes happens but it's not common (and this includes online 'reviewers', too; they have their own agendas.)
imho, the best thing is to look at the non-objectives specs and decide if they fit your needs. Then either rent the product or ask your vendor for a demo to use (or try one out with a vendor that has long term return policies if that's your only real option.) In the digital era with such competition among manufacturers and new 'improved' products popping up every 6 months, I think this is probably the best strategy in order to really answer the questions posed.
p.s., I see refurbished Df bodies for sale now for $2300. That can be tempting.