I recognize a lot of points you mention in your post :)
The 'issue' with the backup window and doing OCR jobs, there is a workaround for this now. You can schedule OCR jobs and have stoptime as well.
If you do casebackups, and only have a short backup window, you probably best set your backup location to the local machine since this can be about 20 times faster than a CIFS network location. After the backup is finished you can then robocopy (schedule) the backup data to a network location.
For every case you have to ask how often the customer needs a snapshot. We have cases with a lot of reviewers where the client would e seriously hurt if they even lose 4 hours of work. This means you have to make sure that every 4 hours all clients are logged out of this case so you can do an individual case backup.
Doing easy full BR/DR is hard! i have been looking at ways to create the appliance where the D drive is an iSCSI target on a SAN that does synchronous mirroring to a second SAN so you could have a warm standby.But if you have a second machine on a standby location, you'd also need licensing for the standby machine.I really hope they would participate in duscussions around availabiliy. It will then still take several new versions before they could actually implement it, but right now i am not sure if they are even considering stuff like this :)