Apart from normal Voicemail, can anyone explain any of the other features/use cases which you can use Cisco Unity for.
For example call handlers, what can you do with them? can it do basic IVR or anything like that?
We use it mainly as an automatic operator.
You can upload your personalized audio and make your own automated attention scheme, so that callers can be taken care of in the best possible way.
Here is attached Call Flow example. You can build this call flow using Unity Connection Auto Attendant (also known as Call Handler). You can record your own welcome greetings, play different greetings for office hours/non-office hours, provide options to redirect call to specific user or to hunt group or to voicemail and so on...
There are many features around Auto Attendant. Based on your requirements, you need to play with it.