I heart vanilla is a good modlist which has some basic bugfixes and minor but faithful graphical improvements. If you wanna make the game look even better, then Volumetric Clouds, Remiros Groundcover (or some other groundcover mod) and Normal Maps for Everything are some of my top recommendations.

OpenMW (or, alternatively MGE XE if you want to use the original engine for whatever reason) already have some nice graphical improvements baked into them though.