I encountered limitations on NixOS, as instance Ly display manager, or using an app compiled by myself. Maybe there are solution but it is not always simple. Archlinux is way more flexible. Updates can theorically breaks the system , but since one year I never broke Arch despite updates on 200+ packages.
Notice I favors minimalist graphic environments (WM that don't need updates ) and minimalists apps as much as possible, such as MPV and nsxiv. I don't fear of some keyboard shortcuts. This philosophy probably helps Arch updates. Sometimes I had problem on apps (Inkscape and Dolphin-emu), I use appimages for them. Nothing is perfect, but Arch put lighter roadblocks than NixOS.