Yeah, in terms of puzzles, it's been interesting with Telwynium trying things much less linear than I'm used to. A lot more puzzles for the sake of puzzles, and characters that are like "I need these 3 things" ha ha. It's less modern feeling for sure. I tend to avoid doing that for the drifter, but it works for a deliberately "retro" one like telwynium. One thing that's nice when you think of more puzzles is that you get more bang-for-buck for the rooms you've done, people can play longer, since it feels like it's a lot of work for 20 mins of play time otherwise! But people don't have as much time to play stuff these days, so I like a condensed experience. Peridium was very similar, just a serious of obvious things to use. But yeah, I like that personally. Just like the flow of "ooh I got the thing, I know what I need to do now". There's a very vocal minority that HATE easy puzzles though :P
My experience writing for these things is similar to yours too, mostly I look back and I can't remember writing most of it at all, such a blur. But one thing I love about these is that you start with nothing and end up with a character you kind of feel like you know somehow.