There are so many ways and differing preferences, but here's a personal experience and a recent discovery of mine
I've always picked with stiff picks. I don't want the pick itself to flex/compress, I want to control the dynamics myself and feel the string resistance.
Small picks was my choice until recently (Dunlop Jazz size or slightly larger). It felt like I had better control with only a small portion of the pick sticking out.
However, as I moved on to playing guitars with thicker strings, and especially acoustics, it just didn't sound good with that small thing. Too wimpy. So I started using slightly larger picks with less pointy tips. Much better sounding. However...listening to recordings of myself, I felt I sounded much too dynamic. As if I lacked areas in between soft and loud.
I was still only letting a small portion of the pick stick out, meaning it would allow for less pick wiggle...as I thought this would mean less movement for my hand, and more control. How wrong I was.
Only in the last few weeks I've started practicing letting the pick stick further out. And in that time I already have more control over dynamics, better sound, AND better and more precise technique! This way, letting the pick wiggle a bit more, makes it slide so smoothly over thick strings, and if I instead want the string to give in (go louder) I just give the pick a firmer grip. I do not have to adjust how deep I dig, so going from soft to hard and everything in between suddenly comes so natural. And that thumb doesn't accidentally mute strings any more

(e.g. when doing chord patterns/arpeggios).
It even seems I move the hand
less than before, and can more easily do large string skips. Kinda like when using a pencil...it may initially feel like holding it right at the tip gives you more control, but holding it further up makes you use less movement and gives smoother lines.
It all begins with “Preparations”
Today, 06:49 PM in Improvisation