Although there were numerous problems with the game (one being the Shadowrun system, which is not suited for this genre), I think that the biggest problem was the high-powered high-fantasy setting itself. One of the players (and a part-time gamemaster) was very upset with bad interpersonal relations in the character group (and I would say that nonexistent interpersonal relations is a better term). He wanted a game of friendship, trust and long-time stable relationships. But it wasn't possible from the very start of the game.
The first big problem came when two characters enganged in a deadly duel. The duel was inevitable. When the Death-worshipper pretending to be a honest healer was exposed, the Sun-worshipping inquisitor had to kill him. Of course, this could be solved by not allowing to play incompatible characters. But the high-fantasy setting (with its often black-or-white world views) is very prone for such unsolvable character incompatibilities.
The second big problem came when my character (the inquisitor) enganged in a suicide mission to save a holy artifact. I was blamed for betrayal of other members of the group. However I felt that trying to desperately save the artifact was a good roleplaying of the heroic fanatic. And it was fun to play such a character for some time, but I wouldn't like to play him forever. A heroic death was a good end for him.
But the real problem was that the character relations were flat, almost nonexisting. And that was caused by the fact that the caimpaign was too high-powered. I think that it is very well described in the rulebook of Call of Cthulhu:
Keepers are justifiably reluctant to allow exotic magick or heavy armament into their games. Contrary to what players might believe, this is not because the scenario might be completed too easily, though that might be a trivial result , nor is it because a Shrivelling spell or a stabilized turret gun might imbalance the game: with oponents like Cthulhu and Nyarlathotep, game balance is unlikely to shift very much.
Introducing higher and higher potency material reduces the chance for roleplaying. The effect of more powerful magick or deadlier weapons is progressively to isolate the owners from the events of adventures and the ordinary challenges of play, and paradoxically to limit the range of responses players and characters feel safe in contemplating. Since the point of a roleplaying game is to roleplay, insulating characters with technology or magick and then introducing greater countering power to re-establish the balance is sad and pointless effort.
Low powered campaigns are usually much more fun. At least for players who prefer actual roleplaying.
