Aesthetically, it seems a bit ... strange. You play a spell, but its effect doesn't kick in until the next turn? Maybe it should be changed to "this turn and next turn" or just "this turn". Alternatively, it could be changed to a permanent that lasts 1 turn (like Sundial) and adds the flaming symbol by your hand at the end of your turn (like Sanctuary).
I guess that the effect doesn't stack if you use it multiple times on a turn?
It looks fun, and has tons of synergies. I like.