This script uses plistbuddy to create com.apple.LaunchServices.plist in the /System/Library/User Template/English.lproj user template. Run this as after in imaging post-flight.
If anyone has any feedback to improve the script I'de love to hear it.
Enjoy!!
#!/bin/bash
# Create the LSHandlers array
/usr/libexec/plistbuddy -c "add:LSHandlers array" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist
# Set default for mailto links
/usr/libexec/plistbuddy -c "add:LSHandlers:0:LSHandlerURLScheme string mailto" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist
/usr/libexec/plistbuddy -c "add:LSHandlers:0:LSHandlerRoleAll string com.microsoft.outlook" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist
# Set Outlook as default for email
/usr/libexec/plistbuddy -c "add:LSHandlers:1:LSHandlerContentType string com.apple.mail.email" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist
/usr/libexec/plistbuddy -c "add:LSHandlers:1:LSHandlerRoleAll string com.microsoft.outlook" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist
/usr/libexec/plistbuddy -c "add:LSHandlers:2:LSHandlerContentType string com.microsoft.outlook14.email-message" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist
/usr/libexec/plistbuddy -c "add:LSHandlers:2:LSHandlerRoleAll string com.microsoft.outlook" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist
# Set Outlook as default for .vcard
/usr/libexec/plistbuddy -c "add:LSHandlers:3:LSHandlerContentType string public.vcard" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist
/usr/libexec/plistbuddy -c "add:LSHandlers:3:LSHandlerRoleAll string com.microsoft.outlook" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist
# Set Outlook as default for .ics files
/usr/libexec/plistbuddy -c "add:LSHandlers:4:LSHandlerContentType string com.apple.ical.ics" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist
/usr/libexec/plistbuddy -c "add:LSHandlers:4:LSHandlerRoleAll string com.microsoft.outlook" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist
# Set Outlook as default calendar app
/usr/libexec/plistbuddy -c "add:LSHandlers:5:LSHandlerContentType string com.microsoft.outlook14.icalendar" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist
/usr/libexec/plistbuddy -c "add:LSHandlers:5:LSHandlerRoleAll string com.microsoft.outlook" /System/Library/User Template/English.lproj/Library/Preferences/com.apple.LaunchServices.plist