It's a shame, then, when Heart of Winter
ends up feeling more like a super-patch than a real expansion. Don't get me wrong -- there's quite a bit of stuff here, more than enough to keep you going for a while (especially if you start the game over) -- but in the end it feels more like an upgrade and less like a true add-on.
The actual area that Heart of Winter takes place in is separate from the Dale, and is reachable both inside the main game (remember that locked cottage?) and separately. As it's higher in difficulty than the start of the rest of the game, it's suggested that you not jump in unless you're above ninth level. There are a few new areas to explore in Heart of Winter, notably a new town (Lonelywood), but the expansion pack doesn't add much more than a weekend's worth of additional play to the original game.
The true improvements crop up everywhere, not just in the new area. There have been quite a few tweaks to the Icewind Dale base game, making it all the more enjoyable. Perhaps the most relevant is the experience cap, which has been raised to level 30. Of course, that's absolutely ungodly in AD&D, not to mention damned near impossible to reach. So a new difficulty level has been added as well -- Heart of Fury mode. If you enjoy getting completely humiliated by a game, then this is the difficulty mode for you.
New spells have been added to all of the classes, making life all the more interesting. Quite a few character classes have gained new abilities (my favourites are the bard songs, but that's a holdover from Final Fantasy IV that I don't want to get into). The various stores in the Dale have had quite an increase in their items, allowing for a large assortment of new goodies for your characters to run around with. And the ever-popular 'bags of collection' to store all of your potions and gems [and cases for your scrolls] are here, so your inventory can be de-cluttered.
To truly appreciate the new features, one must really start the game over. While this is certainly doable if you've never played the game again, those people with time constraints on what they can play may not have the time to play Icewind Dale all the way through again. And a good deal of the charm of the expansion pack is lost.