Kerbal space program 1 mods that make it look modern?

Install the lot through CKAN. Half the trouble with visual packs is mismatched versions of EVE, Scatterer and the texture pack, and CKAN sorts the dependencies for you. Scatterer is the heavy one on the GPU, so if the frame rate falls off a cliff that's what to turn down first. TUFX is nice on top if you want to play with colour grading.

The usual stack is EVE (Environmental Visual Enhancements) for clouds, Scatterer for the atmosphere and oceans, and a planet texture pack on top. Parallax adds ground scatter and proper terrain detail, Waterfall makes engine plumes look like they belong in this decade, and TUFX does the post-processing. Install through CKAN where you can, it sorts out dependencies for you. One thing that confuses people: the volumetric clouds in most screenshots are blackrack's paid version of EVE, not the free one, so don't panic when yours look flatter. All of it together is heavy, so keep an eye on VRAM before you stack everything.