Topaz just keeps getting better, and I use it especially for high ISO/low light shots - high school football.
It's helped me to learn that sharp pictures with subject movement REQUIRE an adequate shutter speed, and with the improvements especially in the sharpening and noise reduction functions, Topaz has changed my approach to photography for the better. I routinely shoot football at 1/1000-1250 sec. and 12,800 - 20,000 ISO, and with careful focusing my shots look really good.
The PhotoAI has subject selectivity, especially for slight focusing errors, and you can manipulate the power of each function - if you ever need to - and switch among different sharpening criteria (motion blur, focus errors, etc.). It's come a long way.

I'm going to just add one consideration not previously mentioned.
Nikon did make a big deal out of enlarging the opening in their Z cameras, enabling lenses to sit closer to the sensor and to reduce the thickness of the camera body, but requiring changes in their optics. The back end of the Z lenses
reach the borders of the FF sensor with a greater angle as a result. And the larger opening would require a larger diameter to the lens.
That may be one small additional factor in "bigger Z lenses," but I make no claims that this is the prominent factor.

These photos triggered my own memory from southern India.
India's famous for overloaded trucks, but "live cargo" was a real surprise.

These photos triggered my own memory from southern India.
India's famous for overloaded trucks, but "live cargo" was a real surprise.

No change unless the newer lens is better.
Since there's no glass in the adapter and auto focus is every bit as good, I've had no reason to think about ridding myself of the older lenses. The 50-200mm f:2.8-3.5 is still sweet!

Very many thanks for providing the inside view of the Dhobi Ghat. This is where all the magic happens, and all that laundry finds its way over the trains back to its owners. All 4 posts are wonderful!

Now that Topaz delivers DeNoise functions through its app, and also through PhotoAI, I really don't worry about grain.
But I do worry about good sharp focus, because that is critical to the quality of the image. Auto focus is key to selecting the right camera for sports, and some sports (low light or highly active play) demand the more expensive cameras. May I suggest that Auto Focus is the difference between a steak knife and a butter knife here.
Good luck with your search.

You might consider simply cropping away the shore line at the bottom, say 1/8 of the vertical dimension.
That removes any distraction it creates and provides the 1/3-2/3 land- sky harmony that some prefer.

I'd definitely save #2 as a "sky" for other shots down the road. Lots of attractive space and great color.

Before you give up on Olympus Mark II, go try some shots at those higher ISOs and do a test of Topaz Photo AI.
And definitely try Olympus' Pro Capture. You can set it up with 10+ shots per second, and use a minimal number of buffered shots, say 3-4 (.3 to .4 seconds elapsed at 10 per second). Hold down the shutter button until you pass the critical shooting moment and you'll get what you want. Then parse through your shots and use Topaz to sharpen and deNoise those best moments. I enlarge those as prints to 20 x 24".
I've been shooting 12,800 to 16,000 ISO night HS football for two seasons with my EM-1 II and a 12-100mm zoom.
And long shots with a Nikon D500 and the 200-500mm f5.6, using Topaz to sharpen and deNoise.
Admittedly, I haven't yet tried my Olympus Zuiko 50-200mm f2.8-3.5. The D500's autofocusing is really fast. Depending on the sport, and the auto focus requirements, the "butter knife" might be just a bit slower.

Travel Guard has always been very reliable and prompt. While you're setting up your trip and calculating how much to insure for, that's the time to itemize and save the documents proving that you're spending the money.
Once you've got that stuff, filing the claim is easy and straightforward.

Honestly, you can define a difference between these 2 terms, but the "reality" out there doesn't change regardless of which lens you're using. If you took a portrait from the same distance, and cropped the 35mm lens image to that of the 85mm lens, the relative sizes of the face to objects in the background would not be any different.

At the same time, the advantage of choosing varied focal lengths is to change the perspective from front to back, either to compress near/far image sizes or to enlarge the near and shrink the far, with roughly the same subject matter in the frame.

I perceive sensor size simply as "cropping" the field covered by a given focal length.

I presume you had a typo, as 128,000 ISO, likely 12,800 right?
Anyway, I have No problem shooting at 15,600 with an Olympus EM-1 II, using Topaz DeNoise or PhotoAI, so long as my shutter speed is at least 1/1000. Don't let motion blur compromise your sharpness! There are also other denoise software packages as well. And if you can, without letting whites overexpose, kick up the ISO and lighten the overall exposure. It helps cut the noise and keeps the shadow detail.

Jules: Allow me to recommend that you pre-select the shots you want to process, and then put only them through PhotoAI. It does take a while, but it batch processes, and this method clears the noise before further post processing. You can grab lunch while it does its thing. Then you can import processed files into LR or PS.

Don't be afraid to raise your ISO. Post processing will take care of the noise.
Do be afraid that your shutter speed is too low; blurry shots - unless very intentionally crafted - are not sharp, not acceptable.
Make sure your exposure is adequate. Don't blow out your highlights, but don't lose the shadows; contrast will be very high.
After the first 3 songs, I envision a wide shot from the back of the entire place, to show the setting, the crowd's enthusiasm and the band in the spotlights. Several bracketed exposures to get it right with your 14mm f 2.8.
Capture the excitement and get their faces. These are portraits, in a crazy situation!
Good shooting!