On this page you'll see a list of the new features added to versions 14, 13 and 12. If the new features interest you, then you should upgrade. Otherwise, if you're happy with version 11, stay with version 11. Why buy a new car if the old one runs fine?
Thanks Steve for the reply, couldn't originally find list of new features..... but will now view then decide
I am doing depth first look and daily discoveries for Premiere Elements 14 and continually adding to it. It may be of interest
Here are few more sources to refer for Premiere Elements 14 what's new:
Comparison across versions 11,12,13,14- Buying guide | Adobe Premiere Elements 14 vs. 13, 12