All over the place or just around certain things frame rate drops?
Are you using any other textures mods? qtp3 meshes by chance?
I don't know if this will help, but if I stand right where the Imperial Waterfront quick-travel dumps me, and walk on the... walkway... like towards the pirate boat (not facing the pirate boat but facing where the walk goes, pirate boat/water off to my right), it's pretty bad. Looking out into the distance, however, is not a problem at all. Standing on the other side of the wall, like where all the shacks are, again, facing the water and looking into the distance is fine, but facing all the shacks and the wall, it's trouble.
Confusing.
As far as I know, the only texture mods I'm using at the ones listed in the helpful install order up at the top of this thread. I wonder if I screwed something up during installation? Pretty sure I did it exactly as was written.
Before doing any modifications, just with vanilla, I had everything turned up to max and got decent frame rates (tho I would sometimes turn exterior shadows down to something reasonable and turn off shadows on grass and what not).