You're not trying to change the habits of other people, you're trying to improve the keyboard shortcuts for yourself. This isn't about getting the GNU people to change the kbd layout for the next major release, it's about making some adjustments to your own personal .emacs file. Erik Naggum called it the "emacs aptitude test", where you have to change the keybindings before they change you. A surprisingly large number of people don't operate with the standard shortcuts.

And what's the downside of customizing this? Not being able to use someone else's Emacs? How often does that happen? (Never mind that you could – for the sake of your co-workers – switch between overridden and default bindings).

As a first simple step: Sticky keys. This way nobody has to hold down any modifiers for a long time. Easily enabled in most operating systems (or with a bit more trouble within Emacs itself).