I am using a 43 inch 4k monitor so I am allin on big screen real estate. But I find that even with a quarter of your screen area, I struggle to read the corners of the screen, the bottom is often obstructed by whatever is lying on my desk, and I had to make the mouse cursor bigger as I kept losing it. I doubt that an even bigger screen would be practical. I do have two 43in monitors side by side but the other one is more like a secondary screen for playing movies or "storing windows", it's too far from the eye to be useful as a primary monitor for reading and writing.
32" being (IMHO) too small and 43" too large, I have invested in a rare (and relatively expensive) 38" 4K monitor (Asus/ROG Swift PG38UQ, ~1000€ when I bought it, hasn't gone down much since), and until now I can only say good things about it. It's big enough to use without scaling (except for a few websites with tiny font size), but small enough so you can have a reasonable distance between the bottom and the desk and still see all four corners without craning your head around too much. It has a fixed foot (only the vertical angle is adjustable), and I originally thought I would have to buy an extra fully adjustable monitor stand, but so far I'm happy with the "default" settings. I'm not getting another one because of space limitations (and spouse tolerance issues), but compared to the two WUXGA monitors I had before, it's already almost four times as much screen space, so that should be enough for the foreseeable future.
Spouse tolerance issues are a significant factor - I have 2 x 32" and my spouse got used to it only after grudging about it for about a year :) If I brought a 43" one, I'm afraid a new apartment with a separate work room would have to come too.
I had a similar experience using a 43" 4K TV as my monitor, it was an OLED so the picture was absolutely beautiful but I'd end up only using the 32" in the middle of the display. I'm now using a 32" 4K display on my desk which is about the sweet spot for me, lots of real estate, and I can see all of it.
I also have a 43" 4K monitor, and I find myself being in the same position as you. The left/right edges are difficult to see. I don't have the issue with the mouse, but I also doubt whether a larger screen would be useful to me. As it is there's a corner that gets unused because it's just out of "eye shot" if that's a phrase. It is now, I guess :D
