Yep. There are lots of hacks for VC. The best guide is
here but there are other tweaks.
This one might help with announcements.
HKCU\ControlPanel\Sounds\TTSAnnounce\Category
change from VoiceCommand1 to Ring
HKCU\ControlPanel\Sounds\TTSAnnounce\Script
change from as5p to v0p (that's v-zero-p) - for vibrate & ring, or p (ring only)
The reg above is to enable announcing callers,it works and it is working
Announcing text and email is just a matter of going to setting/VC/ check option you like.