Something to try for a harsh shifting reverse engagement...
Instead of going from P to R, shift to D first, and wait 3-5 sec, *then* shift to R. I've done this in vehicles with delayed or harsh reverse engagements, and it seems to help (but not outright eliminate) the harshness.
It's actually something I do by habit in all of my vehicles (regardless of make.) It will make the biggest difference on a 'cold' start - when the vehicle is fully warmed up or restarted, doing this won't make a difference (but again, it's a habit I tend to maintain.)
While I can't definitively state the 'why' / 'how' of this, it stands to reason that the harsher the engagement, the quicker a bigger issue will manifest itself, IMO. Also, there is more than one 'cause' of a harsh / delayed reverse engagement, but this seems to help to some extent, regardless of issue.
The harsher the engagement, the more difference you should notice between the two methods.
Finally, on a somewhat different tack, another thing I do when the e-brake lever is in the 'proper' place (e.g.; a hand-operated one,) is to engage it after I come to a stop, but before shifting to P. This eliminates stress on the parking pawl inside the trans (and should help keep the e-brake adjusted properly as well.) You just have to get in the habit of releasing it before you move the vehicle, next time you start it...lol.
Hopefully the above (especially the first 'remedy' above) proves useful to others.