I'm playing on a New 3DS and not an XL so I prefer buttons, stylus is just too inaccurate.
I did look up the passwords earlier and have gotten all of the pokémon from them, so I've pretty much cleared out the first five areas now. One complaint I do have with Pokémon Picross though is that the Alt World is kinda pointless, you can't get any new pokémon there and completing the challenges doesn't get you anything.
That's true, I guess it just artificially prolongs the gameplay. I've only just unlocked it actually cuz I just didn't understand it at first! I probably won't play it again until I've finished everything else though.
In Shuffle news, I finally just caught Thunderus, phew!