Yes, you can use turrets as an alternate viewpoint, but they default to forward when you enter them, and pivoting around every time would be really awkward in battle. The OP is looking for something that I\'ve wanted as well, to be able to turn your cockpits so that you can effectively have rear-view cameras, a docking camera underneath, and cameras anywhere else that you might want to keep an eye on.
Being able to aim a camera backwards can help you check if someone is following you. By aiming one down, you can put it under the core and have a docking camera (allowing you to actually line up with the docking port and THEN dock, which also solves a lot of problems with trying to dock past a PlexDoor). You can also do creative things like having a mining laser that faces down from the bottom of your ship and switching to a downward camera, which gives some aesthetic options instead of always pointing your nose at everything.
EDIT: Or, replace that mining laser with an AMC array or giant missle. You can\'t recreate Independence Day without a downward camera.