sry for not responding so much - Im very busy - just got a few free minutes right now.
Stym, do you access to the art design doc for Rust? Like style ("realism" is a very broad term), and color pallete? Are you making your submissions with both standard and PBR variety? (Per when they go to Unity 5). Do you know the ppi or cm/mm is used in game to get the same textel density?
Nope I have no access - it's all by looking at Dan's and Tom's work and adjusting to their style - Dan helped me out a lot with texture limits and poly limits. Would love to see a design doc or similar on the item admin thing later. I doubt PBR will be used in rust since its Open world - afaik the PBR thing is quite ressource intensive and thus won't work when calculating such a large world - judging from Dan's comment that they are not working on PBR versions of the items yet I doubt they will switch to that (I'm not informed well enough to make a definite call here though!)
About scales I wanted to request scale references from Garry once the item thing is finished so that people can adjust to it - atm I just use low poly counts (as low as it gets to still look good) and use the scaling feature of unity to fit the sizes - especially since my FBX export to unity gives me weirdly small results. Hope that helps =)