Different ways have different effects and choices to be made.
One site / communication channel
As @Akimbo points out, it helps a lot with the SEO. If you're able to give clients another view of you:
full service (...) and you're not just (...) a jack of all trades.
Also, think about what aspect makes you jump out of the competition. Why do people go to you instead of the full-time photographer? What do you do good on all these things? What is your focus in this? If you found this, it would be something to direct your communication and the website around.
I usually think it is better to go for multiple. Then you can indeed completely go for communicating 'photography' on one website and show more of your Flash portfolio on another. The SEO here is also good; though it is not combined, it is more targeted, more specific, more correct even?
But if the different jobs are too small to stand on their own legs, it might not be worth the extra work as you say. You're the only one who can judge that.
According to the Lean Startup methods you could also give each profession its own single-page website and see which takes off. See which page attracts the most clients to use the 'contact us' form. Under the hood, these pages might be using the same website and techniques.
Once one really seems to attract a lot more customers, you can think about turning it into something of its own. Asking clients what they would like more from you in this area, adding other calls-2-action or more pages explaining thing. Adding a new product page and asking people to 'sign up'. If you receive a lot of email addresses for this new product, maybe you can give it a go.