How to scale the graphics for Mac OS
I would download SwitchResX and try the various settings to see if you can find one you like:
https://www.madrau.com/srx_download/download.html
The optimal use for that kind of monitor is the native 2560x1440, however you write that it's too tiny for you. It would probably have been better to get a larger monitor at the same resolution (i.e. a 27&quot; or similar for example).
With the current monitor I would try setting it a resolution that is an integer fraction of the native resolution. I.e. for example try setting it to 1280x720. You can also try 1280x720 HiDPI mode, which should look alright.