Now here is a concept design by Wan Fu Chun that is known as the Puzzle Keyboard, where it will adopt a modular approach when it comes to typing. I guess you can call this a custom keyboard which will fit right into your needs, after all, we are all created differently, and hence, have very different typing styles from one another. Assuming there are a bunch of keys that never feel the touch of your fingertips after all these years, all you need to do is remove them from sight to minimize the entire keyboard. Not only does it simplify the layout, it also helps you make better use of space.
Sounds as though a modular keyboard might catch on, but considering how the extra keys do not create any trouble of sorts even when they are on the keyboard itself, it might not be able to sell too well. After all, there is a learning curve to get used to with a modular keyboard, and sometimes, your brain might just miss the familiar sights of the likes of F6 and F7 keys, in addition to either left or right Shift and Control keys.