Great examples of this can be found with dogwoods. Their different colour stems range from bright red to deep dark purple.
If you have room for a tree or two then some have really interesting markings on their trunks. For example the snake-bark maple (Acer capillipes), a small tree with white striped young branches.
Or Tibetan cherry (Prunus serrula) which is another small tree. It has shiny dark maroon coloured bark, and the bark peels as it ages. Plant this tree close to a path and you’ll find people will want to touch the trunk. Which is great as that helps makes the bark smoother and shinier.