Events such as UNIT_HEALTH_FREQUENT and UNIT_POWER_FREQUENT may have a significant impact on performance. An option could be suggested to let players choose if they want a mode of either e.g. Performance vs. Precision:

• when the player chooses Performance mode, the addon would catch UNIT_HEALTH and UNIT_POWER
• when the player chooses Precision mode, the addon would catch UNIT_HEALTH_FREQUENT and UNIT_POWER_FREQUENT