1) Dell 24 P2419h
2) Viewsonic Vp2468

A comparative of both:
https://www.displayspecifications.com/en/comparison/9c7b99b05

I usually don't play high FPS games like shooters or competitive, so I'm prioritizing image quality.

1) Best color: Seems ViewSonic have slightly better color?

2) Connectinos: Dell also have VGA (which is useful in some cases).

They are pretty similar to me, could you point any difference which you consider relevant?

Also I accept suggestions of any 24" to 27" / 1K to 4K, IPS technology (o similar as Samsung's PSL), to run with a GTX1080.