I have searched high and low for a thread regarding how the NS application approaches the use of email signatures with little success. 

I hope we are not the ones struggling with the lack of efficiencies...or may be we are misusing the application -- we are open to learning about how other sales departments are processing emails to their contacts whether this would be through NetSuite or Outlook (and then manually saving to NetSuite). 

Our issues:
1.  We've had to resort to adding our signatures into NetSuite as Email Templates as we have a standard image we include with the Sales Rep's name, address, and phone number.  The Home > Set Preferences > User Profile > Signature was a "fix" from NS Support.  It only provides text options plus the sales rep must source the Customer:Sales Rep Signature tag in the email.  Not a likely solution, as we deliver hundreds of emails a day.