A handheld spotlight works good for navigation, with a bow mount spot being the best. Tower lights are not good for navigation, just docking and looking good!
The lights on the sides of the boat in the front are just docking lites and dont help for navigation.
If you want to navigate then your looking for a searchlight, they are normally remote control - and expensive, like $5-800. Found one for $250 at http://store.tackletogo.com/acrrcrecose.html