There is a growing arena of places where you can download excellent assets to add to your 3d Library. There’s the usual places like Megascans or Textures.com. Kitbash3d has been adding to their ever impressive city/building library. Another place I recently found is Terrain Domain that is for landscape assets. Some pretty cool pieces available.
A lot of these sites have a “free” bin, so I’d highly recommend at least downloading all the free assets you can get, and then get specific for what you need to add to your 3d Library when it hits your wallet.
Here are two free downloads from Terrain Domain. I downloaded them and hooked up to render in Redshift. They are rendered with a simple RS Dome Light using an HDR image.
The more assets you have the more quickly you can sketch up new pieces with them. I’m currently trying to build a library where I have assets ready to render in both Arnold and Redshift. What I’ve started to have do is have a base Maya file that is primed with a shader to hook up with the new asset. It contains a grey plane, a dialed in HDR and in the top right you can see I’ve setup a diffuse grey sphere, chrome sphere, and a sphere with the assets textures assigned as well.