Nissa, Steward of Elements is a nice abuse outlet here. Cast her for 5 and you can play her ultimate right off the bat if you want, and use her 0 to get any creature costing 6 or less...
I'm not entirely sure that this card needs the cantrip on it. It's plenty good on its own. I'm not sure making your discard an additional cost would make it better or worse, but it'd be a change that I'd consider.
"Keep!"
Legendary Creature -- Elder Elemental
Flash
Flying
1U, T: Return Windspar, the Shifting Sky and target nonland permanent to their owners' hands.
3UU, T: Return target permanent to its owner's hand.
5/5
Instant (C)
Target permanent becomes colorless until end of turn.
Draw a card.
Here's a simple (and short) storm fuel card.
Feed the Storm -- R
Sorcery (U)
Add R.
Storm
Seriously, Limited bomb, we'll see if someone can filth this up in Commander...
Teferi would be my guess...