* Only one class can even learn Dark Magic, let alone GM it - the Freemage

* High level Dark Magic is nowhere near as powerful as in previous MMs - in fact I'd argue that after Expert level, Dark spells are pretty interchangeable with other Magic classes in terms of damage as well as usefulness

* Most of the buffs we're familiar with from previous MM games have been split among the other Magic schools, so Light Magic is more of just another magic option (same as Dark, really)

* You can have both Light and Dark in the same party - even the same character, although not at GM for both (which is another way of saying that the only character than can learn Dark can also learn Light, but not to GM level). This has always been the case since the game launched

Putting all this together, it's not really necessary to GM both Light and Dark the way it was in previous MM games, which would normally open up party choices for those who still like to "max" the party. However, Dark in general contains two very useful spells. Sleep (expert level) is probably the most important crowd-control method in the game, and Detect Secrets (or whatever it's called - novice level) is the only method of finding secret/hidden doors.

As Elf says, you can buy scrolls for Detect Secrets, and there are a couple of hirelings that do it. It's also a reward for a mandatory quest a little over halfway through the game, after which it operates automatically and you no longer need to worry about having it in another way. If you know what you're doing, you can pick up the first hireling and she will last for the first few quests, and then leave after the completion of a particular quest. The second hireling is tough to get to for a low-level party, and there are plenty of other hirelings you'll want to use. So in the early game, where money is tightest, finding secret doors is *very* expensive.

This to me is the largest issue. The only reason not to take the Freemage is to make things harder. If they had given another character even novice or expert Dark - the orc Shaman would seem to be the best fit - this would have significantly opened up party options, and replayability. But as things stand, I've never played without a Freemage, and I never would - the loss of Detect Secrets simply makes things less enjoyable, without any corresponding increase in utility from what the other character would give you

Just my opinion!