Let's face it: I've been spanning the virtual globe in search of the 'right' camera for me. I've been a big fan of big sensors since 2007, but cannot afford to hold on to the largest available when I do acquire one (K-1, D600, α7ii/Rii). The aps-c sensor is my sweet spot, especially since Pentax created such jewels as the DA Limited lenses to keep kits small; for mirrorless though, it's Sony Fuji or move on (Nik/Can have finally staked out places now, but bargains are few with their fresh arrival). Finally there's micro43 and its oft-derided sensor size that just cannot keep up (when examined with a 3x loupe in search of off-color pixels).
It annoyed me when I saw how much interim processing happens with µ43 images to compensate for optics with .. less rigorous optical expectations; since then I've learned that every mirrorless camera plays this game to varying degrees. I prefer the lens to be engineered to make straight lines straight, and all colors to focus evenly across the frame - but it's clear that many do not share my hardline attitude.
I also used to be bothered by the smaller-sensor arguments about equivalent lenses/apertures for a given image.. yet that is not relevant to 90 percent of shooters. If after every shot I attempted to make an exact duplicate of that shot with a different kit, then perhaps it would be relevant. Perhaps.
fyi: I don't do this.
And so, after many kits and brands have passed through my hands, I've assembled a kit with the best stuff I can afford. I've said that before, and meant it then too - but this feels more real. Considering that any camera body made before 2018 is too expensive for me (and still has compromises!), the eM5ii is the newest body with features that I like and use. I had always hoped to grab the 35-100 f/2.8 one day, and now a copy is in hand! The Lumix 12-60 fits nicely below the 35-100 and has suitable image quality. Also I've gathered many small native primes up to 50mm that can be stabilized with the 5.iii (unlike the α6000) so lower light imaging can happen below 35mm. I like the all-manual primes as they are optically designed without auto-corrections; all the camera knows is their focal length for image-stabilizing purposes.
The good sides of µ43 from my perspective:
i. Depth of field control. WAIT NOW, that's what Big sensors are for!! Sure, if you want to blur a background it's more easily done with 'full frame' - but 4thirds sensors can do it fine with f/1.4 primes and the proper distances to subject and background. The issue can be stood on its head just as easily: a 'full frame' camera might have problems achieving sufficient depth of field in some circumstances! Maybe you'd like a fairly long shot where everything is in focus? That's far easier with a somewhat smaller sensor. So there.
ii. Features. I'm not in need of every feature, e.g. burst rates and buffer clearing times are not relevant to a one-focus, one-click shooter like me. Weather seals are valuable though, and in-body stabilization for my primes is very nice. Autofocus in low light might be nice with starry images, capturing photons in real time with screen updates, and interval shooting are things I enjoy doing - well, attempting at least. And video was big enough thing for me in the '90s to carry a DV camcorder in addition to my film camera on multi-day hikes!
At some point I'm going to get better at that again. Whether 4k captures me or HD is sufficient, time will tell.
iii. A noteworthy 'feature' is the 4:3 native shooting ratio, which I prefer to 3:2 most of the time. I also like 1:1 as an easy option. The α6000 offers 3:2 or 16:9 - my two least favorite choices. I'd prefer video in something other than 16:9 too, but that's asking too much of any brand, it seems!
Downsides? Hmm..
I. The flip screen is annoying. I much prefer tilt-types but those are rare once specs for video rise high enough. The tilt+flip style is gaining ground.. but not in my price range.
II. Battery life? With spare batteries and the ability to recharge on the fly, I believe the lesser rated batteries will be fine. The eM1ii/iii last a bit longer per charge, but only the eM1iii and 5iii can charge via USB.
III. (reserved for an as-yet unknown grievance)