I feel as though we should eventually have access to the absolute full potential of our abilities. For example, Alexander would eventually be able to form emotions into living manifestations, though this is a high level skill. Currently he barely knows how to make a solid object out of them, so needless to say creating life with wills of their own, even if temporary, would need a lot more practice in creating constructs. That said, he may also be able to extend his range, or perhaps tune peoples' emotions out, though this is another area of practice and some training with constructs would not affect these abilities at all.
In other words, I think we need to create a tree containing the full potentials and break it up into branches. You can become all powerful, you just need to progress in a certain order, with choices as to what branch you want to train.