Applications (Google Drive, Dropbox, Eclipse, etc) only start when I launch them from within their package
It is possible that this could be a hardware problem? Specifically the logic board.  I discovered mine needs replacing. I am having the same errors. I also discovered that launching the Unix Executable works for many of the apps that otherwise won't load.  This makes no sense to me, but after hearing two Apple Support Technicians confirm, who am I to question.