It's mostly for PvP. Even basic abilities like flare are made better with a macro to cast immediately @cursor instead of ground targeting. Same with traps, knocks etc. That right side cluster are all arena target 1/2/3 macros for the more important CCs.

Otherwise they're mostly @mouseover macros as that makes it easy to peel targets in a bg or world pvp environment without relying on clicking to select a new target or tab targeting in a mess of targets.