I've had both FA and F3HP, sold the FA since I had a K-type 28mm f/2.8 that I couldn't use on it and really just much prefer the heft of the F3. The early matrix metering might have swung me over in favor of it, but due to some cosmic coincidence I destroyed almost every other roll I put through it (think accidental reexposure in the dev tank).
35mm f/2 AI, AIS seem to be quite sought after, this will probably be my next purchase, you probably won't go wrong if you like this focal length.
I finally picked up a 50mm lens (thanks loman), which is the f/2 AI version. Seems nice so far, your E Series should be comparable. Was thinking of a f/1.4, but I'm having trouble focusing as it is (glasses), focus at that depth would be hit or miss. Still, I like to shoot in low light, so it's either that or an SB-17
I also have an 85mm f/2 AIS, which is very very soft opened up, and I'm thinking of selling it and picking up a 105mm instead. Not decided whether to go for the earlier (sonnar) version or the later (gauss). Each seems to have its advantages.