I dunno, guys...

[Alneyan]

Hurray for Slick!

I believe there are two main differences between SE and Dominions:
- Dominions offers much more varied options than vanilla SE, since you will never have an easy access to all the interesting spells/items, and you cannot reach an optimal Pretender able to do everything either (so no such thing as the Clone).
- Where SE focuses on economics, via colonisation, building facilities and improving your economy, Dominions revolves around fighting. Early in the game, you will be facing independents, and later on your fellow players, and conquering provinces is mandatory to have an economical growth of any sort. Consequently, Dominions has far fewer buildings available, and they do not directly improve your economy.

That's a very short summary, as you were probably not asking for a lecture on the differences between Dominions and SE.