While I wait for the arrival of my new lightweight body (I wish!!!) I was poking around reading about the
150-400 lens - not that I'll be buying one as I don't suppose you'll get much change from £10k, but it is a perfect example of "why m4/3?", contemplating handheld 800mm (or even 2,000mm) on a full frame, or even APS-C doesn't get of the physics starting blocks.
I came across the concept of a "Focus Peaking" feature on the Olympus m4/3 system, realised I knew nothing about it and decided it was high time to read the manual, cover to cover. Turns out there are a few features I had lived in blissful ignorance about, and some smarter ways of configuring stuff, not surprising given the soft configuration abilities of most DSLR. Not earth shattering, but useful all the same. Oh, and the "Focus Peaking"? that's the most useful thing and EVF specific, if you use manual focus (or, as I do, AF with MF tuning if you need to) the EVF highlights object edges which pop in and out of definition. No idea why it is off by default, it's a knockout improvement to EVF, like split prism on steroids on a normal VF but operates across the whole frame.
Part of this comes about because I graduated into the latest generation from earlier OM-D models which weren't as fully featured (and optical rather than EVF), moving onto the latest you carry over your old ways of working, and anyway, whoever reads those damn things.
Have you ever read your manual?