***TRIALS RESPONSE***As you're suspecting, you need a different strategy if you plan on outlasting FG's. Now, Firefly Queen decks used to be all the rage a long time ago, and they did kick FG ass back then. Nowadays, they're much too slow, but there's a similar strategy that kind of works. Be warned it still doesn't win a lot, but we can at least discuss the principles behind it.
So what do you need to survive FG's? Looking at the common FG killers, they're usually stuffed with CC or shields while still wanting to retain some speed since it is, after all, farming. So let's look at what shields we have in Light/Air. Wings certainly seems nice.. it lasts 5 whole turns and can protect you from a lot, but there are lot of airborne creatures out there too, so without Web from Death or Aether, we're not getting far. Now, you might think to go Aether/Air and Quint Spiders for Web, but there are still a lot of ways to bypass Wings, and the main problem is this: you will always take damage the first couple turns, you will always take damage when a new airborne creature is played, and you will always take damage when Wings is destroyed or not up yet.
So we need to reduce damage permanently.. there's only one shield in the entire game that can stop that much damage, and luckily it's in Light. What's even better is that Fireflies fuel it. That's right: Hope.
Of course, we can't possibly summon enough Fireflies without FFQ's or other aid, so let's turn this baby into a trio.
Here we have arrived at a basic build of Firefly/Hope:
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As luck would have it, I ran into Divine Glory with it and won after a long battle and her finally running out of Miracles. This won't happen often, as you might know x)
And so we arrive at the second big problem this deck has (first is slowness): since it uses Fireflies rather than Rays like RoL/Hope, it's doing a lot of damage when just keeping the shield high. Therefore, it can't burst past Miracle-using FG's. DG is an exception because she only has 8-attack creatures, so you can actually add Light Dragons for Fractalling in her case.
Regardless, I hope this gave some insight into what's actually needed to tackle FG's. You need a very, very solid defence in most cases. In the case of Aether+Hope decks, you also need at least 2 Lobos.