Ah, everyone should have a pet project, let him have his musings Shin
But yes, I do agree that it's best to look over what others have done in order to help with it and learn all that you can. Then you can expand all that you can on it!
However, there is a major oversight (beyond not looking at what others have already discovered) that is here, that which is (Shin touched and alluded to this via mentioning magnetic and electric -which I usually call Ionic- energies) the Physical Energies, rather than just the elemental ones. I've researched alot into energies and experimented with them, though admittedly I'm too lazy to type it all out (there is a fucktonne which would have to be typed, which I'm not going to do for just a reply as you can literally fill quite a few books with).
There are many categories that you can break up the different energies into. I generally like to split them up into two major categories, the Physical Energies and the Etherical Energies, then split them up further depending on what my current needs are. They aren't the most accurate labels, more of a personal preference to help me differentiate them, but that's just one example of how they can be split up, depending on HOW you are wanting to present them or describe them in a certain situation. For me, the classic cardinal elemental energies would be an example of etherical energies, where as Kinetic and Thermal energies would be an example of Physical energies.
You mentioned Sound/vibrational energy. First they are both physical energies, and second, they are technically two separate energies, Vibrational being one (the rapid continuous movement of molecules/atoms/an object), and the Sound being more of a derivative of Concussive energy which inspires a short burst of vibration through the air (and other mediums, such as liquids and other gases) into patterns and ripples by pushing molecules outwards from a source via a concussive force, which makes it more of a byproduct of something else rather than a full principle energy in and of itself. I didn't describe that all too well the difference between the two, admittedly, as I more gave a very abridged reader's digest version of it and didn't go into alot of detail, but as you see there is alot of things you have to look up and learn and think about.
So as you see, there is alot that you should consider and research which can be of great benefit to you if you wish to continue on this path.