@Piero70
The print time estimates are based on your printers acceleration settings entered into Cura. To reduce the print time estimate you have to enter your printers acceleration settings into Cura. It's not based on the lines of code that you see within the GCODE file.
The issue with unnecessary moves is based on what some of the settings were causing the extruder to do. Not knowing what settings you chose doesn't give anyone an idea of what the problem is. You would need to post your Profile settings file, the STL, the current gcode files, and your printers firmware settings for anyone to give you an idea of what is really going on.
How to export profiles: https://ultimaker.com/en/resources/20441-manage-profiles
This is where you would post your Issue: https://github.com/Ultimaker/Cura/issues
Here is an example: https://github.com/Ultimaker/Cura/issues/3323
Check out the following posts for specifics:
.