Are Airships even needed ? Settlements can build units and you can always leave one ''city slot'' open.
The current airships, as well as jewelers & tailors are a leftover from FfH where settlements are next to useless. I think I will give kurios normal galleons in 0.30, as they do not really need them.
But I like the flavour of flying ships, so I think some should be added as a separate flying ship. Maybe requiring enchantment or air mana? With small cargo and not that strong, possibly stronger in ranged combat (bomb missions?)
I think that the flying promotion should make it such that ground units can't attack them at all unless they fall under these conditions.
* Are an archery unit. Not sure if there is a promotion that shows this but I would think it would be doable.
* Are a siege unit. I would think that the Svaltalfar ballista would be really good at this.
* Are a arcane unit in the sense that spells would work.
The main problem is that Civ IV was not designed to have real flying units. And that is a real design problem. Currently, only allied (and invisible) units can share the tile. If there is an enemy unit, there is no way you can enter. And that would open a space for exploits - ie. a line of flying ships that protect your entire empire because your enemy does not have strong archers, and can't attack or share a tile occupied by flying unit. And that is just one of the problems.
So, Kael decided to go the helicopter route and I think it was a good choice, or at least the simples one. You can always assume that the unit has to land sometimes to let it restock, rest or the crew just needs to pee

I agree, there should be a way to fly over enemy units, but we encounter the same problema as above - sharing a tile with enemy unit, and currently I have no idea how to change that. So all flying units will stay as they are, at least for now.
You could keep the old units though by a clever trick that enhances the flavor of the religion: [...]he illusions would represent the nightmares the opponents have when they face the power of the Old Ones. Additionally it would enable completely different strategies and the revelation spell would finally be useful.
Interesting idea. I think summoning an ilusion might be a good idea, but I will probably limit it to just one - esus is the master of deception and we should tread carefully in this domain.
They should stand out, yes. But I think it would be a mistake to make everything "fit" too neatly, so that AV only get demons, OO only have madness/lunacy, etc. It's those weird blurrings between categories and asymmetries that make FFH stand out so much. Is Basium really good? Are all demons evil? What are those OO really about, anyway? If you aim to answer the last question, I'm afraid you might diminish OO.
I agree, and I do not want to strictly limit things. But for me, drown & stygians are like from a different story. Plus I want the religion to be chaotic, but not necessarly evil (and drown & stygian guards currently clearly are)
So, I think I have a general idea what will I change:
- drowns removed
- lunatics avaliable at message from the deep, reduced to strength 4/4, but with random promotions gained every turn - it might be blitz, +3 to attack strength, or maybe even held (really bad dreams). Should they be still crazied, or should I include enraged to list of possible promotions gained?
- lunatics then can upgrade to priests of overlords, berserkers, immortals & redone stygian guards
- sygian guards are no longer undead or demons, start with mutated (should they retain their initial race?) and maybe some extra abilities (ideas?), plus will pass enraged (temporary crazied?) promotion in combat (just as the diseased is passed)
- OO priests can cast water walking
- illusion summon passing insanity/insanity spell for OO priests
Also:
disciples of all religions get to cast one or two spells - be it sanctify for good ones, and some kind of blight for evil... Plus a religion special (water walking or some low level chaos spell? I think dance of blades should be changed to something more chaotic BTW)
Also, something I wanted to ask for a long time. Should I make Korrina agnostic? There is no sense that she can follow other religions and Publius does not. It can be even argued (but I agree, it is hard to do) that the rise empereor does not need to be agnostic. So, all or none?