The trick with a black bird on dark fabric is contrast, so go for a rich magenta or deep plum instead of trying to out-black a crow. Sketch the bird first with a water-soluble pen, keep the body as simple shapes, and use three strands of floss in satin stitch for the wing so it reads glossy rather than flat. A split stitch outline around the beak and eye gives you that sharp, judgmental corvid expression we all love. For the trinkets, less glue is more. Stitch everything down. Flat buttons get two tiny tacks through existing holes, beads get a single pass through the center, and weirdly shaped objects like watch parts or typewriter keys just need a couple of wrap stitches over the thickest edge. Lay everything out on the hoop before committing anything, photograph it, then rearrange once. You will thank yourself.
Word of warning from experiance, wash your hands before handling tarnished old jewelry bits because they smudge light fabric fast, and knot your thread twice behind heavy charms. They catch on things. Mine survived a move in the car though, so the wrap method holds up fine.