<p>Light is Light is Light....Natural or strobe...it matters not.<br>
Your image quality will follow the quality of natural light if that is all you shoot. Absolutely you should be able to manipulate light! Reflector, speedlights, studio strobes...are all options you should ultimately be employing.<br>
Speedlights modified with a small umbrella are very effective because you are not lighting the subject out of doors you are filling in the subject and perhaps underexposing the bright background with the strobe. How does this work? Imagine a nice sunset where the compromise settings are f5 1/100 (the faces as bright as possible)...With the addition of a speedlight you could go to f8 1/100 reducing the exposure on the background from slightly over exposed blah background colors to a nicely underexposed background...and watch the colors pop! Background too dark? Lower the shutter speed...Not dark enough? Raise the shutter speed! The exposure on your subject never changes!<br>
All it takes is a cheap little Yongnuo 560III, a cheap Yongnuo trigger, an umbrella, and a lightstand...under $200.00 and is capable of world class images. <br>
<br />Light is everything!<br>
Add a second cheap speedlight and you can make the blah day from hell look like a sunny day!</p>