The developer of the very interesting DXVK [GitHub] project has mentioned that the next release is going to do away with environment variables in favour of per-game configuration files.
The goal with this, as the developer said, is to improve game compatibility out of the box for those of you running some of your favourite Windows-only games with DXVK + Wine. DXVK will have some defaults for specifics games (a little like the Mesa whitelist for certain games needing specific tweaks), but it can be overridden by a config file which you can see an example of on their wiki.
Hopefully, this will lead to an improved experience for everyone, since you will be able to quickly share per-game config files if you have one that works better or DXVK itself can be updated with newer versions so everyone can benefit.
Read more about it here, they're looking for feedback right now on games that previously needed some environment variables set.