roses, bouquets and wild flowers
Flowers forgive a lot: a petal a little wider or a little pinker is still a flower. It is the ideal subject for a first chart.
A flower lives on contrast: a yellow heart on purple petals, a clear red against a dark green. Take bright threads for the petals and a slightly duller green for the leaves, and the motif stands out on its own.
A fine backstitch outline draws the petals and gives an illustrated look. Without it, the flower stays softer, more painted. Both work: it is a matter of taste.
DMC references that come up often on this subject, each with its own page.