Seeing as how you have to dash, see your dash startup, then MB to get the dash to turn into a roll, there is no way this will be done on reaction unless you are fulllllll screen. Imagine going through Batarang or Supergirl laser on reaction mid screen. Not a chance.
Considering invincible wakeups are back, delayed getup is back, backdashes are still invincible, and you can do an air ukemi with two different distances, defense will probably be fine. The biggest change to defense that I don't see people mentioning yet is that amongst the four characters, walking forward is significantly faster than walking back, and dashes are not nearly as good in recovery both forward and back.
Also, consider how much easier it is to AA. Fuudo for thought.