I dont agree with the Illu's post. I think the order of the spells is important too. I would use the same spells but.....
This order is more helpful for us:
1. Manaflow (no need to explain)
2. Synergism (a deagro with a damage proc)
3. Cure Arcane (no need to explain)
We mostly use Manaflow, so it should be at first.
Cure Arcane is important too. and on third place its faster and easier to target than on second place.
So put the Synergism on the second.
<Page Name="Illusionist">
<Data Name="Button1" Macro="useabilityonplayer Parent.Target Manaflow" Tooltip="Mana"/>
<Data Name="Button2" Macro="useabilityonplayer Parent.Target Synergism" Tooltip="Buff"/>
<Data Name="Button3" Macro="useabilityonplayer Parent.Target Cure Arcane" Tooltip="Cure"/>
</Page>
Usually on raids, if someone got hitted bye Arcane he tells in raidchannel or in /say, that he needs to be cured and any person next to him is trying to cure him as fast as possible. So i think the wanted curebutton is a good idea for a makro. The other point is that these 3 spells are the only ones that we can use raidwide.