Essential oils that could be used: Tea Tree, Geranium, Frankincense, Lavender, Chamomile. Be mindful of who will be using the salve when adding essential oils as some people can't use some oils and some oils can't be used on young children. Do your research before adding any essential oils.
I live in a hot climate, so this is made with extra beeswax to stop it from melting during hot summers, thus making this a harder salve. You may want to decrease the beeswax to only 2 ounces (56 g) if you live in a cooler climate.
You can test the consistency of your salve by placing a small amount of mixture into the freezer for 2 minutes. Then take it out and let it come to room temperature before testing its hardness. If it is too soft, add a little more beeswax, if too hard, add a little more oil.
You can substitute carnauba wax for beeswax, though it is harder than beeswax, so you will probably need to decrease the amount slightly. Cocoa butter could also be used, though again, you will need to test the quantities.
Vitamin E is optional, and is often added to salves as an antioxidant to prevent rancidity, as well as for its amazing skin-healing properties.