AOTD had the advantage of a true 3D environment, but at the expense of quality in the graphics. SH1 ships were sharper, but I always found annoying how the AOB changed in "jumps". Lot easier to estimate, though
Gameplay-wise both were very inmersive, I have enjoyed both a lot, but as you say the DDs in SH1 were easier to go by before getting detected (Afterwards it was a different story if there were many of them!).
What I didn't like much from SH1 and AOTD -though in this last one it wasn't so exaggerated- was the huge amount of enemy traffic.