I tend to use env variables instead of env files (12 Factor Apps - https://12factor.net/). Safer, not safest. As @late_night_fix mentioned, there has to be a balance.
The main point of hypermedia is the browser, not a gaming platform. Not even the mobile platform. HTMX is not purposed nor it advertises that it should be used outside of the browser scope.
I use Unpoly that replies on the same principles (HTML over the wire) and both of them are very clear about their intentions.
I use Fastmail for my personal domain. The service is great. They don't have a desktop app. I use macOS Mail (which sucks) and, sometimes, I give Spark Mail a try but they are not there yet.
Fastmail do have web and mobile clients. On web and iOS, both are a "webapp" disguised as an app (my guess Android version is the same).
It always depends on what kind of project you're going to work on. My projects usually falls on the CRUD side.
For that, I keep using Django + Unpoly (check it out) + Bootstrap and I always get a SPA like app that works very fine.
And I keep my stack very lean. I'm also a backend developer so frontend stuff is just an annoyance. New language, new build pipelines, multiple deploys (frontend/backend) etc.
I've been using NotePlan (https://noteplan.co) with the Projects + Reviews plugin. It's been a game changer for me. The (almost) perfect combination of tasks + notes.
I also manage my personal stuff with it.
It's a paid macOS app but, IMO, worth every penny.
The plugin was created after users complains. Initially the AI feature was embedded in the editor and there was no way to totally disable it.
That lead to a lot of complains about information security and companies compliance.
Jetbrains listened and created a separate plugin so that people/companies that had issues with AI "looking" at their code and using it to train their AI could keep using Jetbrais tools without that feature.