I cast my vote for series creation. Considering the number of cards currently in elements is relatively small, expanding the card base is a good thing.
Some ideas:
1) Graviton armorer - Ability = "
Neutronium: Target Graviton's HP is increased by 1 and effective hp by 50% for spells and effects for 1 turn."
-> Eg: By effective hp part, I mean that a 6 hp creature would count as having 9 hp when used with catapult, chimera, or Gravity Shield mechanics.
2) Graviton Commander - Ability = "Tactician: Graviton cards have a small chance to deal a random amount of extra damage on attack"
-Extra damage and chance to deal extra damage should be set with stacking and fractal / mitosis combos in mind
3) Graviton Combat Medic - Ability = "
Triage: Heal the most heavily injured allied Graviton card for 3 points"
4) Graviton General - Ability = "
Marching orders: Command target Graviton card to redirect its attack at the nearest enemy in its row."
5) Graviton Tank - Ability = "Armored: Damage to this card from non-poison sources is reduced by 1."
6) Graviton Scout - Ability = "
Military Intelligence: Redirect hostile damage directed at Graviton cards to target ally for 1 turn"
7) Graviton Dreadnaught - Ability = "Goliath: Max HP and attack are equal to the number of allied Graviton Cards in play."