I would like to see the ability to "tap" or completely use shards. Some spells might need a shard as maintenance - the shard is removed from your pool (it doesn't affect spells), but you still get mana for it.

Example: Firey Blade of Might - taps three fire shards, costs 3 mana in maintenance, gives target champion a powerful fire blade (say, 15 + 10 fire damage attack, 50% fire resistance).

Another example: Prismatic Shield: gives target unit a reflect 50% damage ability for the duration of the spell, taps one fire, one water and one earth shard.

(More examples: summon fire elemental/fire lord/death lord/...)

You could also consume shards. Example: volcano: costs 250 mana + 1 random fire shard destroyed. You could go on and spam enemy cities with volcanos - but only as long as you got fire shards. (Alternatively: taps 3 fire shards for 50 turns).

In my opinion this would make shards a lot more interesting. This would also allow for more powerful spells, because there is no way you can spam the powerful spells without having a lot of shards. But, if you have a lot of shards, then you *should* be powerful in magic.