I'm from Mali and shea butter is traditionnally used there for babies' skin. Its color can vary greatly depending on the type of tree, climate, and extraction method. It can be golden, tan, whitish, slightly green or greyish. A good quality shea butter should not stink, if it does it either was unproperly processed or is rancid. It should melt easily, penetrate your skin fast and not leave a greasy residue. Your skin will be shiny after using it but not greasy.
If you find it too thick, you can whip it, or add other oils; if you do not like the smell add some essential oils. I have never seen shea butter with palm oil added, it may exist but I do not know about it. Try to buy the freshest shea you can get, the smell gets bad with time and its healing properties decrease. In my experience, shea butter is more effective when unrefined.
I use it pure or mixed on my feet, lips, hands ans stretch marks. I can use it on my hair dry or wet but not on my scalp, even though it gives a wonderful feeling.
Shea butter does contain latex, so people allergix to latex may not be able to use it.
HTH