Naturally colored soaps 

Natural additives

I make primarily herbal soaps.. I love the addition of powdered herbs, grains & spices both for their color appeal and hopefully skin care qualities.. though, I am still not 100% certain how much remains thru saponification.
Some of the herbs I've added are: Calendula, comfrey, peppermint, all mints for that matter, lavender, thymes, chamomile, alkanet, dandelion flower, sunflower petals, lemongrass, parlsey, dill, rosehips, rose petals, patchiouli, horsetail, delphinium petals, oakmoss, mallow, eucalyptus, sage, rosemary & algaes or kelps.
A few grain additions would be: oatmeal, wheatgerm, flaxseed, orange & lemon peel, carrot powder, poppyseed, raspberry seed & spices... paprika, cocoa, cinnamon to name a few.
Using any of the above will produce a plethora of colorful hues and tones as well as mild to moderate exfoliatives.
I thoroughly enjoy making heat expressed herbal infusions of oils to add to my formulas.

Veggie Oils vs Animal oils

I suppose the choice is a very personal one.. though in researching, each has it's own merit. I prefer veggie oils in my soaps. After experimenting with both.. I find lard soaps didn't hold a fragrance for very long periods of time & the tallow soaps left unscented. had a distinct odor to them. But for a very white bar using no TD lard/tallow would be the way to go.. just not for me.