The only macroes that I use on DPS classes are the following style of Macro:

/ac "Bio II" <tt>
/ac "Bio II" <t>

the above macro is used on my Summoner or Scholar because I usually have the tank pet or the actual tank targeted and if I want to attack with a spell, I will be required to be able to target the enemy without unselecting the Tank, hence the <tt> part of the macro. I can still use the macro to specifically target the enemy because of the addition of the <t> part of the macro, but typically I will not be targeting the enemy and this macro will enable me to still hit the enemy with my offensive spells.

But this is my only type of macro I will use for DPS purposes.