Actually found out it's super reliant on a low density I think? I tried it out on the default bust tool. Worked great but if I deleted the lower subdivs then added one and tried the trick the detail was barely added on.
I looked for it, and in World Properties - PIE game type, you can set this to the type of game you want. For me even by default, it used the UTDeathmatch game type (although that was by right clicking and using "play from here").
It was discussed years ago when the 2.0 theme was the default. The vast majority of users HATED it and through several updates it was brought more into line with the way the old forums looked, as you see it now. It's been debated, a LOT, and it lost.
Burn and Dodge. Press the merge verts hotkey in Maya before remembering to save. Roll the crash dice! Collect 1000's of photoshop and ZBrush brushes/textures/materials only to find the defaults works just fine :P
Swapped out my default modular rock asset with a better, improved one. Watched a tutorial on someone's way of doing rocks, tried it myself and got good results. Felt that the rocks needed more form and shape to them.
If you're using Maya, go to Lighting > Use no lights. That takes away any default rendering done by maya. We can give better feedback if you take unlit screenshots, and probably see the texture flat too :)
I don't know about turning them off, but you can minimize their visibility by (setting roughness up to 1 as you did) turning off Screen Space Reflections in postprocessing and by changing default cubemap to 1 colour.
All you have to do is adjust the near and far clip planes to suit your needs. Just select the camera and go to its attribute editor. I think you can set a default in the preferences window as well.
I think overall this needs a lot of work. The textures look very dated and bland. The default render in max makes it look like you just started 3d 10 days ago. ect. Put it in a game engine.
Not by default, but you can add one yourself: "Customize > Customize User Interface" then choose "UVW Unwrap" in "Group" and scroll down till you find "TV Element Mode". And just give that a hotkey of choise. Hope that helps :)