Poquelin: In Lower Dorn's, I found this an easy fight. If you are protected from fire it helps. Bronze Guardians add to the toughness. But Poquelin is easy to beat first time around.
Easthaven: Cyclopses, not a problem. Pomab is nor more difficult.
Belhifet - haven't done this yet.
HoW - more spoilers!
First thing, when to go to HoW? If you defeat Belhifet first you can pick up the Restored blade of Aihonen and have Tiernon upgrade it later. But if you go to Isacaracht first you can face Belhifet with higher level characters...?
Lonely wood is interesting and there are a few sub quests.
Burial Isle
The Wights and Drowned dead are tough - only constant damage will bring them down as they are fairly resistant to all forms of attack.
Sneak to draw out only as many as you have to - the call to arms will mean you cannot face 1 at a time. So prepare your defences (all those potions you never used in IWD). Weapons and armour should be +3 by now. Try defensive spells that lower your AC or enemy chances to hit (curse, prayer). Sirens - the only way to prevent them really messing you up is with a bard (at this stage a bard means you can also concentrate on defensive as opposed to healing cleric spells). I found my mage really sidelinded. Even turn undead has only a small chance of working.
Gloomfrost
This has to be the most unimaginative level I have ever come acros. Once past the fodder you simply face a level of Rhemoraz and a level of Ice Golems. This is purely to get your characters up levels by 10 or 14K a kill. I mean, sheesh, The lich was 10K!
Magic is ineffectice so its hack & slash time. If you are in dire straits you can really only do things that reduce hits (protection spells) or speed up the hack and slash (haste). Boring. You have to watch out for the Rhemoraz. They do massive damage when they hit and a % chance of doing huge fire damage (they burn thru the ice). I got hit *once* for something like 80+ dmg, 40 odd physical and 40 odd fire damage - both reduced by 30-60% because of resistances!!! At this point I didn't even bother experimenting with magic - each spell is wasted time hacking at the golems/rhemoraz. Ho hum. There are a few nasty occasions where you have to take on 3/4 at a time. Haste (even if already tired) and hack 'em up.
The Barbarian camp is a walk over.
Isacaracht
More boring levels. You need lots of fire/acid for trolls. Protection from cold is handy too - the Vexed Armour is a bonus against the frozen undead. At this point I am tossing +1/2 weapons aside because I just can't be bothered to take them and sell them. Oh dear.
The Sahaguin actually offer a challenge. At one point they come at you in two huge waves (can take them on 1 wave at a time). Kill, retreat to a room and prepare, then kill again. Repeat.
Haven't done big I yet. Then on to TotLM.
Reflection on HoW -
More awesome weapons, items, spells and enemies. But boring. Its like they're dragging you through blood because only level advancement will satisfy.

Too quick. Enemies are powerful and not clever, despite call to arms. In fact, the smaller enemies who swamp you are more difficult (Elves in severed hand for e.g. or Sahaguin).
My mage is weak (considering there are no protection/piercing duels like in BG2). Fighters do stacks more damage. Clerics are useful for the defensive spells but can drop the healing spells if you have a bard. You cannot justify a thief beyond level 9 or 10.
I dare say Isacaracht will be a tough cookie but I know even TotLM will not keep me going. But I've had fun.
[ 08-21-2001: Message edited by: Gruntboy ]