the lighting is very harsh.. try to diffuse the light falling on the subject....no no you don't always need a softbox. you can just use any piece of white cloth to cover your lamp and get a good diffused light. I have used it on $5 lamps and it works
This has potential. The flash creates a glare which is distracting and the picture is a little oversaturated. A greater DOF would also have enhanced the quality of your picture.
This was a good idea and I like the composition. I'm guessing from your photo that the light wasn't diffused. It may also be the characterisitcs of the mango, but it looks a little shallow on dof. Hope this is helpful :)