I sent your question to the rest of the writing team. For now I'll respond only for myself and then complement it later:
1. I'd say my favorite combinations are...
- Pedro, Oscar, Themba, because there's a lot of story and dynamics I want to explore there.
- Themba and Asterion because they have so much history.
- Luke and Pedro, and Luke + an upcoming character, because they both can draw out a different and more heartfelt side out of Luke.
2. I want to write a story about some figures of Brazilian folklore, including but not limited to the pink porpoise, and I really want to write a story in Minoan Crete set a few decades after Asterion's death, focusing on a cast of mythical beings we see represented in some archeological sites -- specifically gryphons, daemons, cyclops (mammoth-flavored cyclops) and more.
3. Yes. This was always the goal. Some specifics changed over time but that aspect was always there.
4. It's a climax, but it's one of the first steps in rising action for Act 3. We're going big. (Mind you, while there'll be other sex scenes, they may even be more intense, but none will be as long as this one.)