NixOS docs themselves are a tad lax, but it will get better.
Learning nix itself is also important:
Just this morning I was having issues with a wacky dual-boot install with NixOS and Windows sharing an EFI partition, and quite interestingly ChatGPT and I were able to troubleshoot the process and get it resolved in under half and hour. I was really impressed by the specific configurations it was giving me for my /etc/nixos/configuration.nix , so that is also another resource you may consider leaning on when you run into walls in other documentation sources.
I noticed that movement combined with a balanced team really helped make higher hazard levels tolerable. For example, you can solo things a bit more on lower levels, but on higher levels having a good combination of crowd control (Driller excels in this) and single-point high DPS (such as the secondary with Engineer) makes it really balanced. We'd set up strats like Driller creating sticky flame traps all over to dump DPS downrange and soften targets while gunner can finish them off, or freeze targets allowing stuff like sentry guns to shatter them. It's really the team cohesion that makes hazard levels easier. When we paired our overclocks together in unique ways it made for easier play through (e.g. intentionally keep to flame or freezing, or, intentionally use both to leverage the temperature shock strat)