As a relative newbie to commuting I was hesitant to ride on roads at first, but after a little practive it doesn't bother me much at all. I only use one section of sidewalk to cross a narrow overpass with heavy traffic. You will quickly find that the road is just so much easier than navigating all of the oddities you find on the sidewalk.

I agree with the lots of lights and reflective stuff on your bike -- both from the rear and the side. You might try adding Tireflys. They screw onto your valve stem and supply a bright blinking light. Since you've got three wheels with 2 sets you'll have one left over to mount on top of your flag pole. That should make you very visible. My guess is that a recumbent trike will be such an oddity that most drivers will give youa wide berth and you may be safer than your two wheel colleagues.