Right now, magic becomes obsolete midway through the game (and so do your heros) once you've researched enough combat tech's.  The spells just don't do much damage.   Also, there just aren't any spells in the game that effect everything in the world.  It would be really cool to have huge spells that could affect the whole world positively or negatively.  Tie it in to the shards.  Require control of multiple shards of the same time.  Have a spell called "Ice Age" requiring control of 2 water shards and costing 50 mana (or whatever), that would reduce food production of every empire accept the casters empire.  Have those big time spells piss off the other factions.  These are the types of spells that are worth starting wars over rather than having everyone just sitting around building.

There were 2 things that made Magic more than Fantasy Civilization.

1.  Being able to create artifacts in the game for your heros.  Making your heros Lords of Destruction was great.  I can't believe that this feature is not in the game.  It took a lot of time and resources to make big time artifacts and it didn't feel overpowered.

2.  Big time overworld spells.  nothing like this exists in Elemental.  Nothing was worse than playing Master of Magic and having one of the AI's cast Armegedon and/or Meteor Storm on the world.  That would immediately prompt you to build a massive stack and go head hunting for that casters capital.  Those spells were nasty, and made the game a lot of fun.  Or maybe you had a bunch of death or chaos books and one of the nature guys cast "Nature's Wrath", and then all of your cities would get earthquaked every time you cast a spell.

At this point, I think I would rather go back and play Master of Magic off of my DOS box.