That and the maps are generaly way too small too, it's setup just for quick DM matches really, whereas A2 can have hueg maps that (with warp disabled) can take ships a good 5+mins to cross, leading to a slower paced game, and more tactical too, rather than just spam stuff to win.
Which also happens to be my RTS prefrence (and if I did it, I'd do it how I liek it.
But mostly cause I know soemwhat how to mod A2, not HW2
Well, the main focus in homeworld 2 strategy does not lay in mindless spam of the strongest unit but in a careful, fast pace micro management of your forces according to the rock paper scissors balancing principal: Fighter squads to hold of bomber squads, bomber squads to destroy caps modules, frigates to destroy corvette and fighter squads, capitals to destroy frigates and so on.
Its actually perfect for resembling the disco mod.
But, you know, I wouldn't say 'no' to an STA2 mod either heh