As a new NixOS user currently set up with home manager and flakes - i'd probably switch in a heartbeat if someone gave me a nice nix-like package manager that also handled dotfiles.
As much as i love the feeling of NixOS, i really want something like a Lockfile as seen in Rust (and other languages).
Ie if i could define a `Cargo.toml`, which includes versions of packages or `*` if i don't care - and then it gets built into a `Cargo.lock`, i'd be in heaven. Combine that with a great language backing the distro and i'd switch immediately.
As it stands, I hate nixlang, and while flakes is amazing i still dislike the single primary input approach to NixOS _(ie all the packages bundled together)_.
As an example of why i dislike that, i'm stuck on an old version of NixOS currently because when i tried to update the repo date - lots of packages changed in difficult to manage ways. X was crazy slow, Firefox was being wonky, XFCE was janky, etc. All my flakes.lock told me was that the hash of the repo was different.. yay.. hundreds of dependencies were different i'm sure, but no clue which ones, and no easy way to isolate the problems and just incrementally update.
Luckily flakes allowed me to rollback perfectly. Well, i still had some userland state from the newer applications that i needed to nuke, but i'm ignoring that for now.
Being able to more easily incrementally update specific dependencies would be amazing for me. As it stands i have no clue when or how i'll update my NixOS input version. Which is not a promising sign for my continued usage of NixOS.