I think what the main point boils down to is will we need to be healing that fast to warrant any macros. If something is fine and we only need to throw out the occasional heal then I think no macros add ons would be fine. From what I have seen this is the way the game is at this time from videos ( although we do not know for sure)
Wow as I know first hand really started to get heavy on macros/mouse overs/ add ons in BC. Decursive was big in Vanilla and some people used Xpearl but that was pretty much it for allot. Once healing required people to get faster, and encounters started to get very fast paced people really pushed their need to do things easier. When necessity is there then the game changes. I think that is why healers especially got very tied up in add ons. In order to make healing easier they needed a way to make it faster.
My hope is that SWTOR focuses on the story and is challenging but not as super spam heal paced as wow ended up.