dtgreene: Druids don't get Turn Undead. Clerics do, and there are a *lot* of undead roaming around. From what I played, the very first dungeon was filled with all sorts of skeletons, including skeletal archers and (IIRC) even skeletal mages. That's probably about as much variety in skeletons as you'd find in a Castlevania game!
Mafwek: Turn Undead was never really good in any D&D CRPG (counting Pathfinder and channel energy as well). You chose Clerics for their spells, not turning ability. And in 2nd Edition, you chose Fighter/Cleric or Ranger/Cleric over vanilla Cleric as well (if you valued efficiency over roleplaying that is).
In Icewind Dale 1, if you play a solo character, you level up faster, and if that solo character is a single-class cleric, I believe you can actually reach the level where your turn undead can actually destroy many of the undead without having to fight them normally. This could, for example, make the first dungeon, which is filled with hoards of undead skeletons; even if you can't get it to destroy all of them, you should be able to destroy the weaker ones, making the dungeon much less tedious.
Apparently, in Pool of Radiance, a level 6 Cleric (only possible for a human, which means you have to be single-class to do this) can destroy the weakest undead, which means you can get rid of them easily and only worry about the actual dangerous undead.
In Pathfinder, Channel Energy can act as a healing ability, making it far more useful, particularly when you're *not* fighting undead.
* Channel Energy is a multi-target healing ability, available (for some classes) at level 1, whereas multi-target healing spells don't appear before (character) level 9.
* Furthermore, it can be used multiple times per day right away, at a level where you don't get that many spell slots.
* There's one class, the Oracle, which uses Charisma for spell casting and can get Channel Energy, whose use count depends on Charisma. So, you can use the same stat for both spellcasting and Channel Energy uses.
* And in Pathfinder: Wrath of the Righteous, there's a mythic feat that adds double the user's Charisma bonus to the amount healed, making it capable of healing a significant amount. This greatly improves healing ability before Heal and Mass Heal become available. (Worth noting that this game has one companion who is set up to benefit from this, although he does have an evil alignment.)
In Dungeon Hack, Turn Undead isn't that useful, but Clerics are useful for other reasons (particularly since this game has spells like Create Food and Water), and there's no Druid class to compete with it.
Carradice: Hi, your post reminded me that when I was taking notes for a new playthrough (still to be made because life happened) I was considering some dual classes, actually. Nice! I will go check that notebook.
Ranger/cleric was a bit curious, since Ranger already has some cleric characteristics. The Paladin also has some of the cleric characteristics and some of the fighter as well. Both adding their special sauces, though.
Mafwek: You take Ranger/Cleric (multiclass) for two reasons: 1) it fights better than single classed cleric; 2) because being multiclassed Cleric/Ranger gives you both clerics and druids spell lists. Sadly, in Icewind Dale it isn't as good in Baldur's Gate 2 because access to druid spells depends on your ranger level, which also means highest level druid spells can't be reached.
In IWD, Rangers do get access to level 6 Druid spells, albeit not until level 29, and if the character is no a Ranger/Cleric, only 1 of them per day. They're still missing 7th level spells.
(From what I understand, reaching these high levels is feasible on Heart of Fury mode.)