Or, you could just use your mouse wheel to unzoom some... that's what I do, and it seems to work well (my screen is 28", so similar to yours).

There's no "unzoom some" for me, the screen can only be in two states:

1. Completely zoomed out:

2. Completely zoomed in:

These are with the default scale value "Adaptive".

What I really need the zoomed in scale to be is (0.60):

But then everything else in the game is too small. 0.50 is even better for the tech screen, but then the font is too small and weird-looking, even though you get a great view of the techs themselves.

I don't like the zoom either. There are only two levels - max zoom in and max zoom out. I wish there was a middle one...

+1 on this. Would be great if the zoom level just had more options. As the default zoom in with all the details is way too close and hard to see anything. I end up having to zoom in and out to move around the tech tree a lot which feels awkward.