Well, I must admit that the vanilla HW2 game is pretty bland...
However some dude (and his team) made an absolutely awesome mod for it, called Homeworld Complex (which is now available on Steam Workshop for the Remaster).
The mod introduced some very nice concepts, like espionage and counterespionage, hyperspace inhibiting to actually secure areas instead of suddenly finding yourself surrounded by enemy fleet, stationary defenses to be dropped in resourcing operations or other relevant strategic points, command levels (for a growing game instead of just overwhelming your opponent with no chance of recovery), slow infinite resources via "mining" for those really long games... and most importantly, upgrades to mothership/flagship to actually survive in the destroyer+ era when damage is just insane.
It really pushed HW2 to a next level !
I hope HW3 will 'steal' some ideas from that mod (or even hire the modder... maybe it already happened?)