Stock Android, the HTC First, and Future Implementations

With the introduction of the HTC First, we now have a smartphone where you can simply revert to stock Android. Should there always be an option to revert to stock on all Android smartphones?

I can see a few problems implementing stock Android. Just because you are going back to stock does not mean that you will get the latest version of Android. The HTC First, for example, will revert to version 4.1.2, not 4.2. So, if you must have the latest version, it looks like you must buy a Nexus device.

Also, would stock Android mean that you lose some features that were exclusive to a particular device? For example, if you revert to stock on a Samsung Galaxy Note II, would you lose the ability to use the S Pen or the micro SD card slot? Hopefully not, but I do not know if stock Android would automatically handle those features. Perhaps you would need to download apps to enable those features.

Finally, I get the impression that carriers do not want stock Android because it gives more control to the customer, especially on features like tethering. I think carriers put bloatware to restrict tethering because they want to block it if you are not on a plan that supports it. Of course, to get carrier-approved tethering, you need to pay more (at least in the US). That alone may prevent more phones from getting an option to revert to stock Android because carriers want to keep that stream of revenue from tethering fees.

So, should we expect more smartphones in the future to have the option for stock Android, similar to how the HTC First implements it?