$60 might be a bit high, but I would consider it for what was listed. At least some of the miniatures would have to be for monsters that were more interesting than Orcs and Kobolds, though. I could see having a number of miniatures that were re-used throughout the long adventure. After all, you don't need a different guardsman mini for the different guards, even if they have different stats.
The adventure would have to be a solid one, though. I would not spend that kind of money on a dungeon-crawl type adventure. It would have to include solid roleplaying, puzzles, and variety. It would need to be something that would keep my interest as a GM and my players' interest as well.
As far as the Spider Queen minis, I had not even heard of them. I wasn't interested in the War of the Spider Queen adventure, myself, since I'm not a big fan of Drow in general. I did like the early Drizzt books, but I haven't read any of the recent ones. I would not even consider spending $25 on 5 unpainted metal drow minis. I prefer prepainted plastic miniatures, as they do not have the assembly problems, hold up well, and do not require my time and limited talent to paint them.
I also think that it would sell better as a Box Set. I personally would be unlikely to purchase the miniatures or the maps for the adventure on their own unless they looked like a very good value on their own. However, if I were looking at the overall adventure with miniatures and maps, I would be much more likely to buy them all in a bundle.