Why was the ability to subscribe other users  taken away from the
administrator in this version in the first place? It was a VERY
useful tool in version 1 that I'm sorry to see go away. Is there
anything we can do to ask that it be reinstated, perhaps in an
upcoming release or fix? The solutions mentioned here may work, which
is fine, but they are fairly cumbersome to implement, and not all SP
admins may have access to the parts of the system that need to be
changed.

Nothing beats the simplicity of the original ability to subscribe
your users to those features you absolutely need them to see. You can
NOT assume that all of them will subscribe, even if you ask them
nicely :)