You could wash the stone in lavnder water as you charge it, that would help with sleeping trouble. I would personally recomend soft coulored stones, such as pale blue or green. Quartz, as you should know, is perhaps the most powerful stone, and probably the best option.
You could also try painting the runes Eolh (aka Algiz)- protction, a shield; and Daeg- dawn and growth, breakthrough, hope, happiness; onto the stone in a herbal oil, such as lavender oil. They are both from the Elder Futhark. Keep in mind they both have more than one meaning, so think stongly about your intentions when doing so, and make sure you paint them the right way up.