Anime/Manga Trends you wish would come back into fashion

For me there are a few.

Series, particularly mecha series, running for an entire year. Not one for everyone I expect but I loved seeing those episodes which were technically needless for the plot but really helped to build relationships between the characters. People don't need millions of hours to tell a competent story but I still feel that shows nowadays are overly streamlined.

Fantasy stories that aren't issekai. Even stuff that felt RPGish ones in the 90s were far more far than what we're getting now.

Space.

I want the "always 13 episode" adaptations to go away.

It seems to be a very current trend, unless a show has huge amounts of content or is wildly popular (IE, a safe bet), that its adaptation will get what I like to call the "test run" of 13 episodes, which will completely ruin the plot or flow of any series that isn't super short.

Also, there was one anime that came out this way and got rave reviews, yet it never came back. That's annoying. So, what's the deal with this, really?

Anyway, I hate filler so I get the new strategy, but why so little with just 12 or 13?