Here's another comparison of screen size thought 'normal' today, and the target we should be aiming for.
1. A 'stylish' cubicle mockup provided by an office furniture vendor in (I kid you not) 2014.
2. With the shortly-to-become-possible larger single curved Ultra HD monitor:
Maybe this suggests a plausible size (at Ultra HD, 3840x2160) and curvature for desktop use. The challenge will be that affordable LCD panels will be designed for TV, and they'll have a sub-optimal curvature for desktop use, i.e. they'll be too flat. But that'll match initial user expectations anyway (but they'll be wrong...)
The larger monitor is TEN times the screen area of the one the furniture vendor thought suitable (I measured the two images...). This example is exaggerated (the furniture vendor is nuts) but illustrates the delta between current expectations versus what should soon be cost-effective.