Well, thanks for your article!
The integration and customizability is for sure not that of Emacs yet, but with the plugin system soon to be merged, we can hope to have a proper REPL and Parinfer implementation!
There is also now a file explorer under <space>+e (little e for starting at workspace root, capital E for starting in the buffer’s directory).
I should definitely use the buffer picker more, at the moment I use the gn/gb commands and it mostly works, but then I suddenly end up with too many open buffers and it's hard to figure out where I need to go again.
There's a file explorer now!
Just tried it now, it's not quite a file tree but it's almost as good.
I have been checking in with helix every 6 months to see if the plugin system was finalised so I could use a real file picker and actually navigate through and explore the files in my project.
That one thing has held me back from using helix. I'll probably give it another go for tiny projects where I don't need any plugins (e.g. in-line error annotations through LSPs, indent rainbow, in-editor color pickers, line sorters, etc...).
OTOH one could build distrib similar to spacemacs/lazyvim, then you could just start with that, and once you find one particular plugin annoying or lacking, you could swap it for something else, at least theoretically (I've never used those personally, so I don't know how hard it is in practive). Not so much with all the eclipses and jetbranses of the world.