Since I posted the above I have installed Suitcase Fusion 6. Illustrator continued to crash at every launch.
I have tried opening with the Shift Option Command keys held down to rest the preferences. No change. I uninstalled Suitcase Fusion, removed all the plugins and tried again several times. Illustrator continues to crash at launch. I have run maintenance apps (Clean my Mac and Mac Keeper), I have also rebuilt my permissions in Disk Utility. No change. I downloaded and installed FontExplorer Pro. No change. I uninstalled Illustrator and redownloaded it. Despite deleting the preferences when I uninstalled Illustrator I now get a window asking me do I want to reopen windows that were open when Illustrator crashed. THERE WERE NO OPEN WINDOWS. When I dismiss this window (i have tried both choices: restore and not) Illustrator crashes.
I have now, today, between 9am and 11:26am AEDST have unsuccessfully tried to open Illustrator 18 times. It is still not open. I can't finish an urgent client project.
Is anyone at Adobe listening??