The first one. Highly saturated colors are fine in small amounts, then it becomes irl pain. They don't even look good in the finished drawing! ç_ç And for the shaded ref, they can't complain if you got their colors wrong since they should have given you a decent ref/color palette (it's not that hard and I don't understand why they do that). I probably won't accept shaded reference without a clear color palette as a rule.
The second one. It's considered even more painful than the first because that awkward moment the commissioner tells you the colors of whatever he/she/it told you to draw are off because they did not give you a proper reference.
while i hate working with saturated colors but i must say i would rather have the color palette than a decently shaded ref sheet. sure i could spend hours trying to remake the original color that the character owner had intended for their character but that's time i could spending drawing in the lines, coloring and shading. i haven't done commissions or anything but i have tried to redraw some of my characters and had no access to the color palette or previous save file and my god was it a time consuming pain in the ass trying to remake those colors.
though i would still work with whatever you gave (to a certain extent) it would probably just take more time.
i don't do commissions though i wouldn't mind doing them after my uni course
When there's a shaded character I just pick the color that looks like the base. I think it's also okay to slightly change the color usage, like sometimes I'll use a more vivid form of the color (cause I like colorful things)
But then again I haven't done a commission yet.
Maybe it's best to just ask the person for a color sheet.
I'd take the one with eyeburning colours anytime - I really don't mind if I don't like how your character looks, I will find it an interesting challenge to see how I can draw them in a way I am satisfied with, and I love to experiment with shading to see what it does to the character's colour scheme. But I HATE unclear reference sheets and having to guess colours. I don't care if your character looks nice, it is a pain to figure out the design and draw it correctly (I always try my best to get the design correct, and when the reference is unclear I just - hnhgn gfbgfbv f)