Agree 100%.  A powerful and expensive pick that you make with your soveriegn at the beginning of the game should not be largely negated through you not being able to acquire a single rare resource.  Those shards should enhance the power of spells in their field (or in any field... say a fire shard enhances fire spells by 20%, and all others by 5%), not be a prerequisite for them.

yes thats nice too

i still like the idea of some "complicated" spell, like an armageddon requiring 5 fire shards and 5 earth and producing again a cataclism destroyed the whole world

i agree with this, this way it would scale on the different size maps.  on larger maps there may be 5 or more shards each, on smaller there may only be 1 each.  this way instead of trying to balance powerful spells based on needed required shards, you get a near infinite ability to increase power through HAVING more shards.

Another idea would be to reserve the Shards for maintaining powerful global enchantments like permanent thunderstorms or an ice age. You'd assign the spell to the shard and it would maintain it until dispelled. 

A claimed but unassigned Shard could cut the Mana costs of appropriate spells in half.

At least this way the Shards would be useful both early and late game and would effectively limit the amount of the really powerful spells.

I think as part of the leveling system (since Brad has admitted he's considering talent trees of some sort) you should be able to talent your Sovereign into removing the need for a particular shard.  IE, you select the appropriate talent and your Sovereign can now ignore the cost of one fire shard. 

You should be able to further specialize to remove the need for more fire shards (you are becoming more in tune with the element of fire) or you could generalize to remove the need for an air shard as well.  This lets you play a caster, and leaves the requirement for shards to cast powerful spells (which I like), but also gives you a way around bad starting location. 

Not only that, but it adds a strategic choice to your leveling up.   You can specialize in whatever school you plan to need to most just as a precaution against losing access to those shards.  It means non-caster Sovereigns will have to consider whether or not their campaign to capture your shard city is really worth it, given that there's a chance they won't truly cut you off from your school of choice.  And if you lose your preferred shard and didn't specialize.. well, sucks to be you.  You could have.

I just want Shards and Sovereigns to be more intertwined. My Sovereigns usually never get within 2 tiles of a shard. They're suppose to be the channelers of the Shards, capable of funneling immense magical energies not owners of a glorified crystal mine.

Bam!  According to the most recent dev diary, shard control will only dictate a few major world ending spells.  The rest will not be contingent upon it.