Idea for a new champ passive and ult

just an idea of a champion's passive and ult not sure what his other abilities should be any input would be nice

At level 1 Azul starts with Arcane type magic. At levels 6, 11, and 16 he may choose between fire, water and lightning each element granting their own bonuses. The elements chosen are displayed in the order they were chosen in the summoner portrait. Choosing fire will grant him 20/25/30% bonus AP and cause all his basic abilities to burn enemies for 20% AP over 3 seconds stacking up to 3 times. Choosing Water will grant him 10/20/30% spellvamp and his basic abilities will cause enemies to deal 10% less damage for 3 seconds stacking up to 3 times. Choosing lightning will grant him 5/10/15% movement speed and his basic abilities will stun for 1.5 seconds (can only be applied once every 6 seconds per champion). Choosing Arcane will grant him 20/30/40 Armor and magic resist and his basic abilities deal 10%AP bonus true damage (applicable at level 6 +). Additionally hitting an enemy with a basic ability will mark them with the appropriate element used for 10/15/20 seconds.

E ~ Elemental Tactics ~ Cooldown .5/.4/.3/.2/.1 seconds ~ Cost 10 MANA Passive: Azul's basic attacks apply the spell effects of the current element chosen.

Active: Azul switches to his next element. Order is determined in which they were chosen.

R ~ Elemental Barrage ~ Cooldown 60/50/40 seconds ~ Cost 100 MANA ~ Range 1000 ~ Damage 50 / 65 / 80 (+ 25% AP) per orb

Azul summons the power of all the elements he has chosen and fires 1 orb for each in a line in quick succession over the course of 1.5 seconds. If they hit an enemy they explode dealing damage in a 400 radius circle. Each orb will be of a specific element and will apply a mark and all spell effects from the appropriate element from Elemental Mastery as if he was using that current element. The orbs fire in the order in which they were chosen always starting with Arcane.