Hello,
It seems to me that we need a few new emotes that communicate sarcasm. We have emotes that convey anger, happiness, sadness, dejection, pretty much everything but sarcasm. Therefore, /slowclap should be added. It would even be easy to make, by slowing down the /clap animation by a factor of 2. Call it mean-spirited if you like, but right now what we have to express a reaction for a minor screw up are anger-based emotes.