I'm not really fond of "customizations" either, lots of code for little value. Having a single toggle for two UIs, the current "CRT" optimized one and a new one focusing on modern format 1080p and 16:9 supporting also 21:9 and whatever insanely wide monitors exist.
The "LED" version would scale well on modern resolutions, be it 720p, 1080p, 1440p or even 2160p. It could also incorporate many of the suggested changes, I can't say I absolutely love the mock ups but they are much much better than what we currently have.
Once the "LED" one is polished we can consider dropping the "CRT" one at some point.