I always felt Homeworld 2 tried too hard to recapture the atmosphere of HW1, which is a common weakness in sequels, "The recipe worked first time, so why not do it again?". The thing about Cataclysm is that it used the same Universe, the same style, but didn't
try to just make a bigger, shinier version of the same story, it steered away from Prophecy and Destiny and portrayed the Higarans more as I would imagine them being after reaching Homeworld, re-fracturing into their various Kith. Without the promise of a future to hold them together, old social habits die hard.
I also hated the auto-end feature in HW2, half the fun of HW1 was trying to build a fleet to cope with the next mission with the RU available (which were considerably more limited in the original). I remember in Homeworld 1 that I used a Cloak Generator and a few Salvage ships on the outskirts of Higara, and managed to capture about 60 Ion Frigates using just those and a lot of patience, drag a few Frigates out of position with Interceptors, get them to chase you about halfway back to the Mothership, and then unleash the power of the Salvage Corvette on them