This is one of those series I experienced as a kid that I assumed was just nostalgia when I grew up. Upon replaying the series plus the new Completing the Mission, I can confidently say that NOPE IT WAS ALWAYS GOOD.
I find it to be very high praise of a visual-novel type game if I manage to like them, considering I don't hold them too highly as representative of the medium. But Henry Stickmin is so insanely funny that it absolutely makes up for the lack of gameplay.
Really the only criticism I can make of the series is that it very quickly became more about seeing the fails than actually succeeding at the objective. But even then, Completing the Mission manages to somewhat circumvent this by playing with expectations both in what does or doesn't work, again, making up the difference by simply being really funny.

Henry Stickmin is the kind of thing that can often be imitatated, but never replicated. Every game encapsulates such a beautiful time in internet history in a wonderful way. It even shows how the creator grew up over time. The first 4 games being so gorgeously and lovingly remastered is so wonderful. Granted, I do miss the more explicit cameos and references to games and movies, but that's something you just learn to live without over time. Completing the Mission is, being honest, a bit of a mixed bag in comparison to the prior games. It's very ambitious and acts as a wonderful finale to every single plot thread the games could've left behind. It's also I feel limited by this and allows for much less interesting experimentation. Still, it's wonderful and campy and stupid in all the same wonderful games the rest of the series is. With ridiculous voice acting mostly done by one guy, genuinely stellar music, beautiful hand-made animation and just being a way to replay and enjoy all these wonderful titles, I wouldn't change this collection for the world. I'm glad it exists and I can rejoice of the nostalgia of my old Newgrounds days at any time.