Cantu Shea butter has a silicone in it so it can cause build up if you are not shampooing your hair. If you are planning to co wash it may be a good idea to find a cone free leave in.
Have you tried a water and glycerine spritz sealed with an oil? Some people love glycerine others hate it. As you have an interest in curl activators I assume that you don't have an aversion to glycerine based products. If you haven't already tried it you may want to see if your hair likes it.
It may also be a good idea for you to baggy your hair after you apply your moisturiser. This is a good way to help the moisture penetrate the cuticle leaving your hair soft and moisturised.