RE: Firelord using his "flame-body" defense
While that is a good tactic, and will at least initially work, Diana can look for a window of opportunity to use a high speed charge attack, with her bracers crossed for the Aegis effect (as she did vs. Ares massive power attack against her in Gods of Gotham) and assault FL that way; she doesn't have to remain still, or anything like that, to use her bracers broader power, and that would help mitigate FL's fire-defense.