You should not set up a Y resolution higher then the screen resolution.
I use 1080p because then i have 4 pixels for each scanline and additional enough pixel for the TV border itself.
I still don’t know what you mean with warped pixels on the X axis.
I can’t see any difference between 1194×896 and 960×720
You’re right the exact aspect ratio is 1194.66666 in the X axis but with 1194 every emulated pixel is 4,6640625 pixels on screen, not 1, in practice i can’t see the difference, especially with the scanlines
Also most shader have either more or less recognizable effects on the emulator speed. For example SNES Yoshis Island first level, first cave.
The sharp-bilinear.glsl do nothing at least on my tests.
Instead i use the video_smooth option in the retroarch.cfg.
The same with the pixellate filter.
In my opinion the pixel edges and the scaliness itself in your example looks too sharp and too dark for me, it looks not really realistic.
My TV border isn’t 100% finished yet, it’s a bit too much curved, so in some games too much of important image details are lost, but i like it ;-)
Here you can download some fullscreen scanline overlays and another with a TV Border
And here is the Youtube Video: