Have you got a major insect problem in the rest of the garden? What insects are worrying you particularly? Which particular herbs were you going to grow?
Most herbs are pretty robust - especially the mediteranian based ones (thyme, rosemary, oregano, etc). If you can kill off mint you deserve a gold star. Once you've planted chives they'll self seed all over (easy enough to shift, but they certainly haven't been decimated round here, and I have plenty of slugs, snails, greenfly, etc).
Tomatoes - I guess it depends how high a yield you want and how perfect you want the fruit to be. I grew a couple of cherry tomato plants one year and (IIRC) I didn't spray them with anything or give them a huge amount of TLC at all other than a good drink every day or two - I doubt I'd have won any prizes, but they tasted great and I could barely keep up with eating what did grow. I was working full time.
There are products out there that are environmentally friendly and/or organic and will help with an insect problem - but unless you KNOW you're going to need them or will be devastated if it happens, why not just see how things go and deal with it if you need to? A lot of insects can also be removed with the finger and thumb method (squish) - as long as you're not too squeamish....
How much care does your DH think veg and herbs need?