I like Starfire. She's compassionate and protective. For Hot Head, I would probably go for something like this:
When attacking with Starfire's normal attack, you may choose up to 3 friendly figures within 3 (clear sight) spaces. Add 1 to your roll for each chosen figure. Figures chosen for this power must have at least 1 wound marker on their card.
I'm just thinking of younger players and how to read a power in order, broken into small sentences.
As for the Blackfire synergy, I would suggest keeping the flying thing, but an extra +1 if the player controls any Tamaranian figures.
I did read the 80s Wolfman/Perez run years ago, but haven't seen Blackfire much since, so you go with what feels more thematic to you.
PS - You're Austalian, Matt's from the US and I'm from the UK. I nominate this venture as Helmsverse League International (better let Matt be Blue Beetle though
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