There's another aspect to this I haven't seen mentioned. (Granted, I haven't read every post.) Weight balance between the wheels. I started my adult life at 6'1/2" with long legs and very long arms. I come far forward (if the bike allows) when I stand. I also sit forward on the seat both going hard on the flat and on hairy descents. So, bikes with either short front ends or long rear ends (again, for me) will be light on the rear wheel. Any dirt on the road and I skid the wheel climbing standing. Bumpy corners on descents are scary. But a bike with a long front end and short chainstays solves both these problems for me. (Well, bumpy cornering takes some other things being right also.
So, just getting the fit right does not necessarily get me a "good" bike. I take this seriously. Before buying a bike, I measure up the frame, draw it up on my CAD program overlaid with my other frames, see what I need for stem and seatpost to get the fit AND locate my center of gravity between the wheels. For me, very few frames pass both criteria. For most it is a matter off how much "not quite right" I am willing to accept.
I'd wanted a titanium bike since I did a quick ride on a Merlin in 1990. Early auts I created a program that calculated the needed stem and seatpos plus weight balance from the specs in brochures simply to quickly see what titanium bikes were worth investigating further now that Lightspeed, Merlin and others has several models and I was in a place where I could afford a $4000 dream bike. Eye opening. $4000 wasn't going to get me a dream bike, just a "B" fit or handling. So I now own two ti bikes that do it all but I had to pay the extra k for custom.
And all this has taken me (well, one bike) down a rabbit hole. Long top tube and front end, steep-ish to get the handling I love, short chainstays all seem to add up to high speed shimmy; not a major problem 14 years ago but now in my late 60s, I'm not as strong or fearless and have become part of the problem. (I thought I was doing myself a favor by getting a bike long enough that I could ride it with a 120 stem for perfect fit. Easy to find plus every racer of my generation knows Eddy Merckx and God both rode 120s. Now I know my ridiculously long stems on my other bikes are reliable wobble dampers.)
Oh, I could solve some of the weight balance issues by simply sitting further back on the saddle. Yes. And have a bike where I have to watch how I'm riding and force myself out of the sweet comfortable place my body loves to keep the bike happy. So instead of it being "my bike", I am the bike's "rider" and I am supposed to do what it wants. No thanks. I raced a bike long ago that worked perfectly without me making any compromises. I want and expect that.
All that said, I just purchased a 40yo frame from a forumite, Japanese race bike. I know a couple of measurements, no angles. Rust and $75 so not a lot to lose. I'll measure it up when I get it, stem and post accordingly, throw some parts and wheels on, ride it and see if it's a keeper. What I do know is that I have owned two Japanese race bikes of that era that were sublime fits. Maybe this Pro Miyata will share some DNA with my old Fuji Pro. If it does, I might be riding this rusty mess a long time!