Pandora - great promise - in my experience crappy execution. I tried a bunch of times to start over - it's pointless - their AI algorithms still managed to screw up royally every single time.
What issues do you have? I have a lot of stations on Pandora that I have been thumbs up/down on for a few years and I get pretty good assortments of music, with new music added as a new musician pops up as similar (or a new album from a previous favorite).
I am moving slow, but it is looking like my end game will be playing Pandora through my phone whenever I am in my car (which has Android Auto) because I run the free version and don't notice the shortcoming of the MP3 sounds very often with road noise.
At home, I expect to eventually run a hard drive from my PC or a NAS (welcome your thoughts on that).
A couple of examples/tips on using Pandora:
1) I love "The Only Exception" from Paramour, but really don't want to listen to punk more than something like once every 5 songs (given good punk). Accordingly I would make a station from "The Only Exception" by Paramour rather than a Paramour station.
2) I love Big Band music, but not so thrilled with recordings from the 50's and early 60's. Accordingly, I have a BBC Big Band station (the BBC put together a band later (maybe early 70's, but the recording quality is consistently good. I'm sure I had to thumbs down a few songs that had sad recording quality, but it did not take that long to get it to where I like it. Alternately you could use Gordon Goodwyn's Big Phat Band as the seed (or basis) for a station..
3) I like early Genesis more than their later more pop stuff (which I still like). Accordingly I have a "The Lamb Lies Down" station which predispositions towards the earlier music.
I'm not sure everyone knows that you can use an album or a specific song as the basis of a station and it doesn't have to be by the group!
That gives me an interesting thought, I'll have to set up a station based on the music from Miami Vice TV show, I know there is an album with assorted musicians, but think I like most all of it!.