interesse: do they improve the game in any way or is it just more of the same? obviously they add new stuff like a new race, i would see that as "more of the same" i am wondering does it improve the a.i. or revamp some features in the base game that the fans were not happy with and that were not otherwise tackled with a patch?
i am totally new to the series.
Well its been a while since I played the game but they add more variety to the game.
For eternal lords: 1 new class, 2 more races, New songs, and extra races is always nice to see. Other than that the page for the expansions state there is a new victory condition added, racial relationships and a new story campaign. There is even more than this.
https://www.gog.com/game/age_of_wonders_3_eternal_lords Golden realms is quite a bit smaller with one new race and an added campaign, more songs more maps, etc.
To answer your question: It adds more to the game. I'd like to note that all the fixes to i.e. the AI, just came as a standard patch for the main game. The expansions add more to the game, not just expand it but also add more mechanics. People missed the racial relationship system which they added in the expansion. Note that you do not need the expansions to play with/or against people who do have them. If a friend has the expansions and sets up a game with a victory condition found in the expansion, you will play with that condition as well.