Re: Useless or redundant units?
 

Most of the points I would have made have been made above, but I'll add a few minor ones:

Flying units are not necessarily only used in combat. They patrol much more efficiently than their earth-bound counterparts, they siege more efficiently, and they can be used in raiding parties to strike behind the enemy lines, taking out the comparatively easy provincial defense instead of the main-line armies.

Sacred troops are priced according to their potential effectiveness, not their unblessed stats. As someone above noted, an air blessing on the Guhyaka/Yavana can get them through the rain of arrows to combat where their reasonable defense skill (often much better than protection, especially if you are outnumbered), Awe (!), and high strength can make them effective. There is also the Yavana archer, the only long bow recruitable in the early era as far as I know, with an incredible precision of 12 -- give them a fire-9 bless and you have an astounding artillery capability. Finally, the Guhyaka is recruitable anywhere, not just in the capital, which makes fielding massive, blessed armies possible... and this should also be factored into their cost.

Re: Useless or redundant units?
 

*ahem* Fire bless doesn't affect missiles....

...but Quickness does allow them to shoot about twice in a round, and the +affliction chance of death bless affects missiles also.

Flying units, those with superhuman stats excluded, need microing to be effective.

Re: Useless or redundant units?
 

Fire 9 doesn't affect missiles. Water 9 and Quickness does, though, and as even Yavana Archers have Awe and decent defense, they have some survivability in melee, and their high strength offsets their low-damage attacks.

Death 9 is also interesting in that the 350% affliction chance also works for missiles.

Kailasa can also summon better sacred units later. Gandharvas are armored. The unarmored ones are still a nice addition to those forces.

Re: Useless or redundant units?
 

Well, you learn something new every week or two.

Re: Useless or redundant units?
 

The description of "flaming weapons" spesifically mentions "melee attack". Death Weapons don't work on missiles either, but the increased affliction rate does. Flame Arrows work, of course, but Kailasa will have a hard time getting that... It might be worth it, though. They have lots of archers.

Re: Useless or redundant units?
 

Yup. Also, Dominions assigns the other traditional light cavalry roles -- scouting and raiding -- to other units, but leaves the traditional high cost of horses.

Re: Useless or redundant units?
 

Let's just make a mod to remove all light cavalry, perhaps excluding ones with light lances. Would anyone cry ?
Some of them are even available only via magic sites ! Horse brother - wow !

Re: Useless or redundant units?
 

Impossible without deleting poptypes. Or replacing LC units with other units. Which would be hard, because the same LC types are found from different poptypes. About the only thing you could do would be to #copystats and #copyspr an archer or something to their place. In which case, there wouldn't be anyone crying. However, I'd rather buy Light Cavalry than have no archers.

Two suggestions, which probably wouldn't work:
Give all LC Stealth 0. Evil Dave mentioned that Light Cavalry aren't raiders. They could be.

Give LC better capabilities in moving across the strategic map. Mapmove 4 and/or all terrain survivals, or something similar.

Re: Useless or redundant units?
 

The idea of redundant or worthless units keeps popping up but there isnt much agreement on what they are. What you think of as worthless might better be phrased as "worthless for the way I play". Check the differences and see if you cant come up with a strategy or tactic which might rely on that difference. Slightly cheaper, or better morale, or different weapon or armor.

Re: Useless or redundant units?
 

Gandalf: for a start, try finding good sides of Light Cavalry. It's a hybrid of light infantry and awful archers, with mapmove 3. You don't pay 25 gold for an awful archer. You don't pay 25 gold for light infantry. There's no synergy between these two. If we exclude mapmove3 (Lion tribe infantry is just as fast!), well... You can probably Have one unit squad of light infantry and one squad of archers for the price, food, and upkeep cost of LC. And before you say LC is more flexible, you can send squad of LI and Archers in two different directions.
What I'd love to see is tactical purpose for Light Cavalry. Giving them stealth or pillage bonus would be nice, but does nothing to adress their battlefield uselessness. With the unrealistic +2 precision I proposed they could at least try fire&retreat, without risk of being engaged in melee. I don't think few volleys of overpriced( = low in numbers) archers would accomplish much, but it would be a good start.
I understand you have much more experience at this game than me. You should be more capable of finding a real use for Light Cavalry than me. I know many spells, nations or units eventually turned out to be quite useful in their niche, but LC is not one of them. If I'm not mistaken, Light Cavalry has consistently very little actual value since Dominions:PPP (which I didn't play).

I was toying with a mod idea. I wanted to implement early Dragoons (soldiers who'd go somewhere mounted, dismount at destination point, and fight as infantry). But I see very little point in that. As far as I know, foot soldiers have no advantages over mounted units in Dominions3. I could give dragoons Tower Shields and heavy infantry armaments, but I'm afraid the battle engine wouldn't benefit from extra mobility, if simple light cavalry can't.
As for dismounting mechanic, I could use shapeshifting.... if only I could attach arbitrary effects like shapeshifting to weapons, and make them shapeshift into footmen upon attacking something...