If you want a more traditional look, I guess that you mean like a realistic painting, then it is too dark and light IMO, the value (which is more important than hue BTW) goes all the way from black to white.

The hue (or "color") seems to be chosen more for style than for representing a real nut/fruit, in nature usually nothing is very saturated, it's quite dull! So try out some dull brown colours and try to make what you can with them. That's what you do when painting, maybe you can try it out digitally.

As you are doing digital, you can check out values by switching your painting to black & white (just removing the saturation doesn't work well).

I'd put in a background too, could be a dull color, but that's just me :-)

Good luck!

I really like the tones and blending! Only critique I can think of for this particular style, is that the outline feels a bit too dominant, especially on the side of the shadow. What I would try there would be either (a) blending the outline into the shadow, so it is one shape instead of the subject + shadow divided by a line, (b) use a color for the line that is closer to the hue of the subject, rather than mostly gray/black or (c) experiment with line weight a bit. Just some thoughts, I hope it makes sense :)

It looks like a peeled garlic clove

Depending on what app you used, you can make it more authentic and traditional-looking by adding a paper texture layer underneath and setting the blend mode to overlay or multiply.