These aren't curated playlists, they're just a collection of any new songs I discover and really like, or old songs I re-fall in love with. I then give each playlist a name that references how I feel or an event that happened that month. I was in a similar place to you a couple of years ago, but I've found doing this really helps me track my tastes and experiences every month, which I find is quite helpful in our streaming-dominated musicscape.
When I used to actually download songs, it was easy to scroll through my library and be reminded of artists I'd forgotten about or had only listened to a couple of times. I've found that with streaming its really easy to lose track of who you listen to and enjoy, so it really flattens everything and causes you to either rely on the algorithm or your go-to past artists.
As far as discovering new artists goes, there are still a few reliable sites and publications that review new albums (paste, gorilla vs. bear, pitchfork (sort of), etc.). I also like following or signing up for email newsletters (gasp!) from specific indie record labels that I enjoy. If you like several artists on the label, then chances are you'll like more, and they always notify you when something new is being released. Same goes for local venues. Check out the small stage acts coming through or various openers, even if you don't actually make it to the show. This is also a great way to get plugged into the local scene and it keeps you young, sort of.
