When it comes to portraiture I am 100% in favour of natural light. It took me lots of money and lots of hours to realise that given the chance, my lights stop in the bag. There are times when you just need that little extra though, so learning to control light artificially is a skill that is never wasted. I used to get intimidated by strobes until I realised that I could use them to compliment natural light. It's all horses for courses though. :)