First, let me apologize for not having read each and every single post before this, so I might be reiterating a few things.
It's worth noting that the version of HeroEngine that SWTOR uses is so old that the DirectX 9.0c support is just bare bones. It's really just a DirectX 7 engine with some tacked on functions. The most tell-tale signs is that a lot of filtering an shadowing is done via CPU instead of GPU, how it struggles to handle FSAA and how it completely lacks multi core support.
SWTOR tries to get around this by separating the rendering engine from the main process, but as people with state of the art graphic cards can see, this doesn't really bring much in the way of performance.
Another problem is the sound engine. I confess: I have -no- idea what they use, maybe it's part of the HeroEngine package. What is obvious though is that what we get, is 8 channel stereo sound without panning between the channels.
Try a round of space battles and you'll notice sound starting in one speaker and cutting out as it appears in the other, and sound stuttering when all the sounds fight for the access to the few channels available. This is like going back to the days of DOS games.
Even if I'd love DirectX11 support, I'd be glad if they just patched in the new engine to get better performance, not even including anything DX11 specific. It will most likely be a night and day difference in performance!