Sweet marjoram is one that I find to invaluable. Its excellent in massage for muscular aches and pains, spasms, arthritis and related problems and brings instant relief. I have been treating a client with chronic upper back pain very successfully with this in a synergistic blend with roman chamomile and lavender.
It is also good massaged into abdominal area for digestive problems and intestinal cramps.
Also a powerful relaxant, excellent for insomniacs, a few drops in a warm bath before bed and/or burn in vaporiser in bedroom before retiring. Can be blended with clary sage for a stronger effect.
Blends well with bergamot, clary sage, roman chamomile, lavender, rosemary, citrus oils, cedar wood. But I also use my oils instinctively.
Go with your instincts.