It's free, easily available, readily playable without having to change your system locale or use appLocale, and it's mostly decent.
Also, sentimentality. Seems a lot of people started with it, so people tend to recommend it.
I wanna say Ping Pong the Animation.
Its art style will let it remain timeless, it's largely unconventional, and since it's not simply just a sports anime it will have wider appeal I think.
Also, Gurren Lagann is still within the last decade, so that.
I mean, it's so overused that it's become almost a non-word by now. Which is amusing, since in the comic it originated from it doesn't have any meaning to begin with.
Option 2, if only because it's been ingrained in my head that download links for things go at the bottom of the page - for some reason. Also the space breaking up the text is nice.
Watched The Boy and The Beast earlier this morning. Visually appealing and a nice setting, but a bit overly long while still being rushed in some aspects. Story was pretty generic as well, as far as anime goes at least.
I'll throw Killer Queen out there, since you seem to have a thing for death game scenarios. Not a huge fan of that VN myself, but it's short enough that you can can comfortably form your own opinion on it without wasting too much of your time.
Personally though, I'd give Grisaia no Kajitsu a spin since it seems that you haven't read it.
That's a tough one. My first inclination is SW:KotoR or Vampire the Masquerade: Bloodlines (it's the game I've replayed the most out through the years), but I actually think MGS3 might just win out overall in terms of complete and utter adoration for every aspect of the game.
I'll leave this here:
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