Active and Passive Spells - Modification and addition of actives and passives promotes diversity in builds.
Elemental Spells - Increasing spell experience adds diversity to builds.
If you are going to use a deck system, why not eliminate spell experience all together and have them level similarly to passives? Otherwise, restrict the deck only to actives and passives leaving elemental spells as they are.
My 0.02 Kamas after my first look.