Picard was good for fan service but not much more. I watched all of it and the writing was underwhelming at best.
Mandalorian was good for fan service and quite a bit more. Honestly, as Disney's first live action Star Wars show, I was pretty impressed. Particularly considering they didn't lean on the "Force" for any of it. I am a fan of the writing and the directors they used as well.
WandaVision is surprising. If you haven't watched any of it yet and you think you might, I would advise preparing time to binge it in like 2 or 3 blocks. The episodes are on the shorter side and they spend a great deal of time laying out all the cards before they start revealing their hand. People who say they are bored early on, I completely understand. Marvel took a risk here in my opinion and did something unique, and I appreciate that, but damn does it test your patience at times.