I made and tested a couple of new macros tonight. I find that I am not very good about using short-cooldown trinkets and spells, and so I decided to try and come up with macros to use these automatically.
Holy Light Macro
#showtooltip Holy Light
/cast Divine Favor
/cast Divine Illumination
/cast Holy Light
This macro attempts to cast Holy Light(Rank 11) with both Divine Favor and Divine Illumination. I'm a Flash of Light spammer, so when I need to pull out HL11, it's usually worthwhile to pop both these cooldowns.
Flash of Light Macro
#showtooltip Flash of Light
/castsequence reset=10 Holy Light(Rank 5), Flash of Light, Flash of Light, Flash of Light, Flash of Light, Flash of Light
This macro attempts to pop both my trinkets whenever I cast my Flash of Light. This ensures that I get maximum usage out of my trinkets. The castsequence is so that HL5 keeps Light's Grace up fairly often.
You can adapt this macro so it works with any spell you spam (Fireball, Sinister Strike, etc.):
If you use these macros, you should go into Sound Options and uncheck Enable Error Speech. Otherwise it will drive you mad. Note that text error messages are cleared before you cast the actual spell. This is so you can see "Out of Range" or other useful errors.