In this series of posts, you'll notice I'm using only one oil in my creations...I don't generally do this in lotions as I like to have a blend of oils that offer exactly what I want for the weather, skin type, and application.
A light oil will sink in quickly (or at least feel as if it sinks in quickly) and offers immediate softening and a nice feeling on your skin. A medium oil will sink in a little slower and will last longer. The heavier oils will stay on your skin, giving you some occlusion and protection from the outside world. A combination of all three will give you the best of all worlds in a lotion, and I encourage you to formulate your lotions with at least two different oils for maximum awesomeness!
I always think of recipes as templates that can - and should! - be tweaked. I always make something by the pattern or recipe exactly as directed the first time, then I play with it to find the perfect product for my skin type and climate. I think one oil lotions are a good way to find out what you like (or dislike) about each oil and what it feels like in a lotion. Then you can combine them to make something amazingly fantastic!
Have fun playing!