I only went 64 bit with Office 2013. Now I am using 2016. Most any plugin we se here is for Outlook, for meetings, IM, and our ticketing system, and they all play fine with 64 bit Outlook. 64 bit before Windows 7 was flakey on the OS level, let alone the apps, but I've been running 64 bit Windows since 7.
Outside of some third party stencils for Visio, the only other plug in of any sort I have is a custom script I wrote for Word to update the document variables in out standard documentation templates. ANd that because I am lazy - the default in Word updates either the body or the headers and footers, not both in one operation. So I created a simple script to update the entire document and stuffed it on the menu with an icon.