It sounds a little bit like introverted and extroverted versions of cognitive functions. It could be interesting to see those additions play out, but I'm not sure that they would add much (if anything) new to the types that isn't already there. One could argue that iNtuatives work from abstract to concrete and that sensors work from concrete to abstract. One could also argue that Fi is more focused on inner morals (because it is) and that Fe is more focused on outer morals.
So the trouble here is finding something new that this fifth preference (and remade fourth) add that is worth disrupting the previous system. It is, however, a cool idea. I've often pondered the possibility of a fifth preference.