I know there are tons of better shaders out there, but my all time favorite just due to its customization features, how natural to the game it looks, and how lightweight it is for how good it makes the game look, is definitely Slidurs Vibrant Shaders V1.22. I have a configuration for it that makes it look so good at night & day. Not too dark, not too over contrasted, not too bright, good on frame rate. I will follow up with screenshots
Also if you would like the configuration I have let me know, I will be glad to give it out. *FYI All posted screenshots are a build of mine for a server I am working on*