I'll run Font Doctor again and re-inspect my active fonts in Suitcase. But it's odd that this occurs only in Safari and only in my iCloud front page.
Well you're odd too, but it's a Helvetica font conflict dood, I'm tellin' ya'.
Safe Boot not only clears font caches but it also turns off all non-Apple fonts, and stops third party stuff from loading, like Suitcase Fusion Core.
Set Suitcase to not start at startup, also see what fonts are located in Users/you/Library/Fonts and Library/Fonts. If there are any move them out, move them to folders so you can put them back if needed. Do a Safe Boot to clear caches. Reboot back to regular. See if the problem is still there. If so check in System/Library/Fonts and see if you have any non-Apple fonts in there. Make note of any Helveticas.
, it will tell you what should be in System/Library/Fonts.
Here's a good linktoo. http://www.jklstudios.com/misc/osxfonts.html
It explains how to remove protected fonts, ones the great Apple deems necessary and replace them with your own versions
Do a search on that page for 'Removing Helvetica, Helvetica Neue and Helvetica Light', it will take you to the directions for removing the Helveticas permanently. It says Leopards, but the next section covers Lions.
BTW it may not be a conflict between Helveticas, it may be a Helvetica that you activate that is corrupt in some way. I know, you ran FontDoctor, but I've found that FD is not 100% reliable, and I have found it to break fonts that it says it fixed.
It may also be a Font ID number conflict. The system is trying to use Helvetica #123456 (ex.) but that is pointing to something else.