As a long-time finger-style guitar picker I recently learned to use a plectrum when I took up mandolin. Inevitably one thing led to another ... yes, there's "pick acquisition syndrome" as well ... and I've now got a couple of dozen different plectrums, most of which are actually used, but all on different instruments.
For a nylon-strung ukulele (I'll include Aquila red's here, I use them so I can), I use a thin nylon pick, 0.46mm on a soprano up to 0.73mm on my baritone, for melody work, a
Jumping Cow artificial felt pick for strumming on all of them (note to self, must order a spare).
I also finger/thumb pick and strum as the mood takes me, but that's by-the-bye for this conversation
I've tried harder picks, I don't like the tone, but that's on an acoustic instrument, YMMV on an electric. However, I would have reservations about using a harder pick on nylon strings, especially for strumming, as it may cause excessive (and uneven) wear on the strings, possibly giving tuning problems before they prematurely snap. That aspect of things may not concern you, that's your privilege and I don't have a problem with it, but I thought I'd mention it
Whatever you do, enjoy it ... it's not called "
playing" the ukulele for nothing !!