There's already quite a lot of good recommendations here. I'll just add another voice recommending Kino's Journey and To Your Eternity.

Also, I'd say don't expect Frieren levels of polish and awesomeness with the recommendations given, as Frieren is just a different level altogether (with lots of deserved hype).

As for my own recommendations? Let's see:

• Aria the Animation, Natural, and Origination — this is but one anime series with three seasons of varying length. Every episode is more or less self-contained, but the characters develop slowly over the span of a lot of episodes (I counted 72 for all three seasons, could be wrong though). In a way, the character growth and exploration here is more comparable to real life. The pacing might be a bit too slow for a lot of people though. and the overall tone might be a bit too sweet for some. There's some world-building here, but it's really subtle at times—with the episodes focusing instead on the everyday and sometimes, the supernatural goings-on around the city the characters live in.

• Natsume Yuujinchou [Nastume's Book of Friends] — six seasons of varying lengths. This is also mostly episodic with some character growth happening but the kind that you'd easily miss just watching the episodes. This one, however, has more supernatural themes, but also touches on how the youkai (non-human entities--to put things simply) differ from humans not only in mindset, but also in their perception of time.

• Mushishi — I haven't yet watched this one in its entirety, but this is favorably compared to Natsume Yuujinchou, and so it might hit the same notes as that one.