Where's your sense of adventure? lol
I have a sense of adventure, my point is that GB giving you some "adventures" by randomizing stuff will kill what speedrunners are looking for.
That said, Diablo 3 just added competitive speedrunning to the game, but due to randomization your results vary greatly from attempt to attempt. At least they always just keep your "best" time, but still the results of the guys at the top of the leaderboards will be affected a lot by how much luck they had with randomization during their record-breaking run. It's fun and all, but not what true speedrunners would be looking for.
Just look at any speedrunning video and you'll get the idea.