1. Ultravision lost a great deal of usefulness with the (needed) change to darkness. One with the Land seems the spell closest in power that affects skills, and it grants +4 to a number of skills. I'm going to suggest that UV also grant +4 to search and spot as well as the somewhat cosmetic change it already grants to your vision. (Looking over various sources on the web, I even see one that lists a small bonus to lore, since you can see uv light that enchantments might give off... eh. >_> Glowing eyes anyone?)

2. Darkness clearly needed a change since it broke the AI. However, it's been reduced to even less usefulness than current canon darkness. Mainly, I regret to see that it's no longer useful to a stealther whatsoever.

Previously: Blindness/invis effects (50% concealment), breaks line pf sight completely, allows entering stealth, though fixed location and short duration. Also broke AI.

Canon: 20% concealment, allows stealth in places you could not normally stealth, moves with the caster, can be switched off at will (it's cast on an object you can put away), long duration. (10 minutes per level)

Now: 20% concealment, short duration, fixed location. Combines the limitations of pre-fix Darkness with only one advantage of canon Darkness.

So the suggestion is simple, instead of a stationary effect, it buffs the caster and surrounding allies with +4 hide to approximate the useful concealment effect on stealth in canon, as well as a 15% concealment for 10 minutes per level. (Slightly reduced from 20% as it would not have the drawback of miss chances on melee opponents.)

3. Darkness domain power. Currently it's Ultravision once a day. Suggestion is to make it unlimited uses per day, it's caster-only anyway. Alternatively, caster-only removal of blindness seems appropriate. Sword of Omens, give me sight beyond sight! Rawr. Temporary blind fighting seems fitting as well. More so than having a "adjust your screen gamma" button in-game rather than a domain power. Discuss. >_>

Edit: Another idea for Darkness might be to let the user ignore any area-based penalties that apply to stealth, due to lit areas. In other words a global sort of stealth bonus, equal to the area's stealth penalty, applies if that person is under the effects of Darkness. It wouldn't help in areas that are already darkened, but places that are well-lit won't reveal someone who's in a shroud of their own darkness quite so easily.

These suggestions all have merit, especially the first one. My only worry is that I heard somewhere that custom Domains can't be changed.

:(

The effects can. The hook that the domain has can't but the script it calls can be edited to your hearts content I believe.

I do not like the idea of Darkness as a buff.

I'm also pretty sure Ultravision is one of those things like torches and other light sources where, deep in the engine, they're taken into consideration for spot/search/hide.

I do not like darkness as a buff, however-

The notion of casting darkness on a group of archers across the way, and making them unable to see until they left it, was something that I thought was one of the greatest spell usages in NWN.

I think having a (somewhat significant) bonus to hide might be interesting as you could cast darkness, sneak to one point, cast darkness, sneak to another point, etc. OR use it just before an attack to hide in and strike out from the darkness. Hide is useless in combat anyway so it's only good once. The problem is that it would be impossible to see camouflaged small race rangers.

Darkness shouldn't be yet another rambo-cleric buff, couldn't agree more. That's why I'd like to see it regain at least a shred of usefulness for it's obviously intended purpose: infiltrating/escaping. If it only counter-acts area-specific stealth penalties, it won't really make camouflage much more powerful, nor would it if you made them use the same stack tag or whatnot. As far as the concealment bit, nerf it down to whatever seems appropriate, 10%, or ranged only? Fine with me.

Heh, ultravision... let me just say that I personally can't remember a single time anyone has ever said before venturing out of Sanctuary, "Gosh it sure is dark down here, do we have enough torches? Maybe you could read up on whipping out some ultravisions instead of those itchy combust spells."

I can't argue there shouldn't exist spells that are, for nearly all practical purposes, useless, because if DMs decide these should be left as are, then that's the way it should be. But by gum, as the spell stands now, it's for all practical purposes useless, and if you wanted a pretty useless spell for it's casting level to make better (read: people actually use it), well this is it. :p