Titanium restore vs. ADB restore. Which one is better after a system update?
I would prefer restore apps using Titanium, for the reason that it gives you total control on which user apps you want to restore.  In your case restoring system apps is not a recommended option since you have upgraded OS. It would lead to a mess up. Hence, while restoring choose the option of restoring just user apps with data. Answer how to restore only user apps is covered here 

As a general guideline, best not to restore system apps after upgrading or changing ROM. After changing ROM also it is better to verify and update only those user apps which are not included as system apps in  new  ROM. You may often come across this situation while flashing Gapps recommended with new  ROM