Piano is actually somewhat notorious for being excessively baroque and difficult to play at the higher skill levels, the keyboard having been originally designed to play only in a single key with a different tuning system.
Basically, when you play music aloud naturally with your voice or acoustic instruments where you have complete control of the pitch, people tend towards using whole numbers for representing harmony, like 3:2, since it sounds the best. Unfortunately there are 12 notes in an octave in the Western music system so you end up with bad ratios if you want to use instruments which are tuned to play anything more than a single key. If you are in complete control of your pitch, like with voice or violin or other stringed instruments, the all of the players can adjust their intonation on the fly when the keys change, and still keep the nice whole number ratios.
Enter church organs, which are huge, expensive, and can't be tuned while they're being played. But they're very nice and impressive. So they were tuned to play in only one key -- C. That's why the keys representing the scale of C major on a keyboard are all white, and the other (less important) notes are smaller black keys. You won't be pressing these very often, better to get them out of the way.
Then along came some math people who calculated tables of compromises that ended up giving a pretty decent sound to harmonies, but was laid out in a way so that you could play different keys without having to adjust your tuning or intonation. There were different systems, but they were referred to as having temperament. Hence the name "Well-Tempered Clavier" in the famous composition for keyboard instruments, which made ample use of the newfound ability to change keys whenever one pleases.
So now there are a bunch of keyboard players who can suddenly play in any key they want with the new tuning systems. But the keyboard layout is still same one used for playing only in C. That all happened hundreds of years ago, but we're still stuck with the original layout for keyboards.
It sounds rather like the origins of the QWERTY keyboard, which was designed in the late 1800s to minimize mechanical jams when the typebars swung up to hit the paper but persists to this day due to lock-in.
QWERTY was designed as a compromise between speed and jams. Characters which are frequently used as pairs together are placed on opposite sides, one for each hand. This has the effect of letting you use both hands pretty frequently. One of the compromises was that only the vowel 'a' ended up on the middle row. 'Maximally efficient' layouts like Dvorak are not provably any faster under real conditions.
As a Dvorak user, I can testify that, while it may not be faster (I didn't have an appreciable speed increase after switching), it sure feels more comfortable and natural when you do most of your typing on the home and upper rows, and common key clusters fall nicely in pinky-to-index order.
