Try AM's blog and their fragrance calculator. It looks like you could add some wonderful Eo's for bug repellant suds!
Notes from Bramble Berry About Lemon Eucalyptus Essential Oil:
Lemon Eucalyptus Essential Oil: The aroma has a strong camphoric bottom note with a refreshing lemony top note similar to citronella. Lemon eucalyptus essential oil is an ingredient that's key to some of today's leading brand natural insect repellents. It's a wonderful alternative for those wanting to avoid insect repellent that uses the chemical DEET. The EPA has registered lemon eucalyptus essential oil to be safe and as effective as low concentrations of DEET. The EPA also states that this essential oil can repel those nasty little critters for up to 6 hours. Suggested usage rate is 30-40% in sprayable applications. It's also used in aroma therapy applications for it's relaxing qualities. It can be added to lotions, soaps, or facial cleansers. The aroma pairs well with wood or citrus essential oils.