MoO1 and 2 were two of the very very few space 4x games where you could actually finish a match in a reasonable time by winning or loosing. While Galciv2 and SotS matches tend to drag on for forever. Something that just kills the fun and stops me form starting another one after i technically won/got a stalement in the first.
MoO games also gave you alot of tactical option while designing your ships.
Something which is especially lacking in GalCiv2. Ok it got some cool ship designer for the looks but gameplay wise it was just about adding the right attack/defense ratio with your best tech onto the hull.
While SotS got it better i always end up with some alrounder design which i just keep on updating till the tech tree is exhausted. Mostly because special designs like cloakers or drone carriers got some real hard counters.
In MoO1 you
1. could not just upgrade to a better tech cause it there are no simple upgrades to existing weapons and better tech always needed more space
2. may have to change your designs because your enemies ships where too small/shielded or simply killing your ships too easily.
MoO2 failed to recreate the though.
Now the only weak points of MoO1/2 are the luckbased starting positions having alot of impact on the game, the extensice micromanagement in MoO2 and the AI which was kinda weak but playing unfair.
In MoO1 it was allying with each other far too often and got some bugged 32k ships fleet on harder difficulties.
In MoO2 it always seemed to have some kind of strategic range bonus and always knew where you ships where flying, always hitting the planet which was not defended well enough. The only defense was offense.
Which were honestly the only things stopping you from winning too easy (after you put tactical battles on in MoO2)
But the better AI of modern game(partially due to more computational power of modern pcs) does not help them to overcome their poor core mechanics.
Now if you want to know why Galciv2 is not better than MoO1/2 then you have to look into
-the economic system aka the reason for "all-x" strategies
-the spy system + larger maps+mass spy event+not spamming counter intel buildings=NOT FUN
-the, as far as i know of, still broken twilight AI, with certain races
-occasional tendencies of the AI to play unfair: when trading techs or finding colonies(i heard that was fixed)/resources/anomalies, note that you can reproduce that by sending your , for example, flagship to auto survey. it will directly fly to the nearest anomaly in range no matter if you can see it. if it is flying to a point you can be 100% sure that there is an anomaly there.(which may be found by an AI first though) And if there is none it will just sit somewhere.
Just think about that: why should it sometimes fly to some unexplored tile and sometimes just sit there tellling you that there is no anomaly in range?
And this auto find algorithm seems to be used by the AI for other things too.
-the "cool" is better than "balanced" game design strategy which led to alot of the weak points in galciv2. ok this is a singleplayer only game where balancing does not seem to be that important, but in order to provide entertaining and varying strategic challanges, the skill of the player should be THE factor which leads to win or loss and not some random balancing of the techs he used.
my 2 cents