I think its going to be difficult for any RTS to match the complexity and micro management of MoO3. From my perspective its difficult to compare the two. They are different animals so to speak. I can tell you that the economy is MUCH easier to use in Sins than it was in MoO3.
You do research technology to build better ships and equipment. You can research planetary shields, fighter defenses, and such for your planet defense. Im slowly getting used to using tactics in my fleets too, ya just can run in a opponents system with 50 ships and expect to win. Your ships also earn experience, which improves their HP, damage, and special abilities.
its kinda early though to have the in depth storyline and such things, they gotta get the core functions to work right first however they are adding more and more content to the game each time theres an update.
I myself really enjoy the graphics/eye candy and have a difficult time going back to MoO. Although id really want to see true planet destoryers in the game (and then a way to reassemble them or asteroid belts into useable planets) id still play it if it didnt.
Thats just my views though, im not a stardock guy

just a gamer.
void