It's very hard for any game to create a convincing morality game element, most of it usually turns into a DnD style min-max setup, where your moral choices are picked to give you the biggest advantage, not because they're good or bad. This is said on the assumption there would be game changing mechanics for being good or bad. If there is no reward to play good or bad, then there's no reason to pick either. ...
Some of us who got into RPGs before IBM's first PC hit the market got into them precisely because they were games that could be great fun without any min-max stuff, and I've known other PC gamers who have a similar attitude about civ-style games.
Certainly, many players will have a fundamentally competitive approach to Elemental, even folks who only want to play against the AIs. What I'm trying to type about is the idea that actions should have *interesting* consequences that are based in the game's internal logic (cosmology). One of my greatest peeves with GalCiv2 is that it has an 'alignment' system that's mostly useless for the min-max crowd because Evil is the best choice if you're into high scores. Ditching alignment entirely is one way to fix that problem, but I'd rather see something, ahem, 'balanced.'
Depends what you call "ethics".
Aztecs had temples and they were sacrificing their prisoners by the thousands. (not to talk about churches and Inquisition, or indian Thugs and kali temples, or any ancient nation loving to raze and burn cities... )
The Aztecs are a great example--they're the kind of culture I was thinking of back when I hoped to see Life and Death magic have meaning beyond visual effects and spell lists. Those ritual mass murders were most certainly 'ethical' from the Aztec point of view; the fact that they were almost incomprehensibly horrible to the Spaniards was an essential part of how the Conquest unfolded.
But I can see how folks might get hung up on my use of 'ethics' language. I'm using it in a casual social-scientific way, not in an attempt to invoke any particular real-world set of values. As the Aztec example points out, real-world ethical conflicts have diplomatic consequences. I'm not particularly hung up on seeing the stuff described with specific words, I just want the mechanics in place because the 'RPG dimension' of the game will seem flat without them. Simply lowering the XP return for a mass-NPC-murdering sovereign won't make any meaningful difference. Each sovereign needs a reputation and the AIs need to be able to respond to those reputations in ways that reflect the identity of their factions.