Even though I have introduced magic missile into my Dwimmermount campaign, I actually share Sean's perspective on the matter and somewhat regret having moved beyond the spell lists in the LBBs to include those from Greyhawk. I think there's a lot to be said for keeping to the lists in Volume 1 of OD&D, both in terms of game play and esthetics. That said, I don't think all the spells introduced in Greyhawk are problematic or game-changing. Here are my thoughts on a handful of the spells I do think alter the dynamic of the game in ways I don't much care for:
- Legend Lore: I prefer that forgotten knowledge only be obtainable through research, which is to say, scouring old libraries and visiting far-off locales. Spells like this obviate the need for lengthy journeys across the setting -- and thus adventures.
- Monster Summoning: I am deeply ambivalent about this collection of spells. On the one hand, conjuration is a classic wizardly trick, but, on the other hand, there's something about the ability to summon -- and control -- monsters to do a magic-user's bidding without any strings attached that doesn't sit right with me.
- Silence 15' Radius: Depending on how one interprets the spell, this is potentially game changing. I've allowed its use in my campaign, but wish I hadn't, or at least I wish I had interpreted it more narrowly than I did.
- Speak with Dead: I am ambivalent about this spell too. Again, a lot depends on how its interpreted and, while I am generally happy with the way I've allowed it to be used in my campaign, I have issues with it esthetically, particularly in campaigns, like mine, where the nature of life after death, including its reality, are open questions.
Now, I'm sure one could create a setting that followed through on those implications -- most D&D setting do not -- but my gut tells me that such a setting would be very different than the default pseudo-medieval/ancient world most referees and players assume when they hear the words "Dungeons & Dragons." And I'll admit that I'm skeptical that such settings would be very workable as places to adventure in the conventional ways, but I am notoriously small-minded. Regardless, I don't feel any compulsion to allow spells of levels 7-9 in my Dwimmermount campaign. The range of power presented in the LBBs is quite sufficient for my purposes and I've actually come to think the introduction of those higher spell levels led to a lot of later mischief that the game would have been better off without (such as the notion that magic-users were "overpowered" and that other classes needed to be beefed up in order to keep pace).