Be brewed some light beers with fruit extracts added into the bottling bucket and keg which came out good but I've never been able to extract the fruit flavor from adding natural fruit into the secondary. Any recommendations?
What kind of fruit flavors are you looking at? I've had great success using various Knudsen Just Juice products. I use one bottle for a 2.5 gallon batch and 2 for a 5 gallon batch. It's pretty spendy, but it's easier than using fruit and the results are far more consistent.
A lot of the flavor from fruit is because of the sweetness which all ferments out. You can backsweeten if you keg, or better is add some sweeter specialty grains and mash a bit higher to get a little more sweetness to bring the fruit flavor back out