I don't seem to have much problem with macros, it's finding ones that line up well. This is easy on homogenous groups, but a lot more complex on multi class ones (i.e. do I want the button to cast curse of agony on my warlock and moonfire on my druid? etc)

Do you guys spend lots of time thinking which spells to put on which buttons, or do you just say 1-6 is for my priest and 6-= is for my warrior (or something along those lines)?

I just try to minimize the amount of different buttons I need to use.