digitalis - flash or no flash shooting

I would just like to show the difference. thou the no flash pics are most likely shots i made long time ago. since for almost 3 years now i always use flash to shoot portraits and macro.
One thing i like with flash is it do make shooting fast and easy. but if make the subject exposure very harsh :(

without flash

Model NIKON D80
Shutter Speed 1/320 s
F-Number f/5.6
ISO ISO 100
Exposure Bias Value 0.00 eV
Metering Mode Pattern
Flash No Flash
Focal Length 60 mm
Lens Model 60 mm f/2.8
White Balance Details Auto
Date/Time Original 9/28/2008 10:51:37 AM

Model NIKON D80
Shutter Speed 1/250 s
F-Number f/5.6
ISO ISO 100
Exposure Bias Value 0.00 eV
Metering Mode Pattern
Flash No Flash
Focal Length 60 mm
Lens Model 60 mm f/2.8
White Balance Details Auto
Date/Time Original 9/28/2008 10:51:12 AM

Model NIKON D80
Shutter Speed 1/125 s
F-Number f/5.6
ISO ISO 220
Exposure Bias Value 0.00 eV
Metering Mode Pattern
Flash No Flash
Focal Length 200 mm
Lens Model 18-200 mm f/3.5-5.6
White Balance Details Auto
Date/Time Original 9/16/2007 11:10:03 PM

with flash

Model NIKON D80
Shutter Speed 1/200 s
F-Number f/9
ISO ISO 100
Exposure Bias Value 0.00 eV
Metering Mode Spot
Flash Auto, Fired, Return detected
Focal Length 60 mm
Lens Model 60 mm f/2.8
White Balance Details Auto
Date/Time Original 10/8/2015 10:09:43 AM

Model NIKON D80
Shutter Speed 1/200 s
F-Number f/29
ISO ISO 100
Exposure Bias Value 0.00 eV
Metering Mode Spot
Flash Auto, Fired, Return detected
Focal Length 60 mm
Lens Model 60 mm f/2.8
White Balance Details Auto
Date/Time Original 9/6/2015 7:56:57 AM

Model NIKON D80
Shutter Speed 1/160 s
F-Number f/8
ISO ISO 360
Exposure Bias Value 0.00 eV
Metering Mode Spot
Flash No Flash
Focal Length 60 mm
Lens Model 60 mm f/2.8
White Balance Details Auto
Date/Time Original 9/6/2015 8:15:56 AM