My humble opinion:
If you want different cameras: let the player choose.
But also be aware of the consequence that the option of choosing the perspective has:
- a 3rd person perspective requires good animations on characters
- a 3rd person perspective in small indoor environments requires a good collision detection between camera and obstacles
- with a 3rd person cam a player might be able to see stuff that you can't see from 1st person cam
(I guess there are more)