I have often noticed that excessive reminders tends to slow things down. By excessive I literally mean dozens an hour. The alternative of course is to use the task list. But some-how many users are not happy unless they get to close the reminder window every 15 minutes.
Another is turning off the reading pane and the preview pane. It might not seem like much. but those two, slow down managing e-mails when you are moving things around and organizing when it has to open up each e-mail when you click on it to move it.
Like everything else when taken to excesses. Having hundreds of rules to help automate organizing your e-mails can slow your outlook down.
I agree with 1&2 #3... archiving your inbox is great however in many cases that just means you have 2 pst files instead of one and many use it as a dumping ground,
#4 is almost necessary if your exchange server is offsite.
#5 & #6 are absolutely necessary for those with huge PST files
#7... Hmmm never knew anyone that had more than a half dozen
#8 Also I have never seen an issue with slowness due to the feeds
#9 The Achilles heel of any program... Plug-ins and Add-ins Some are great but you never know they are a problem until they are removed.
Keep Up with TechRepublic