Thinking of getting rid of the plug and just wire this direct. Will this be OK?
you can wire it without the plug up on the bow, but you do need to have a way to disconnect the trolling motors power when charging the batteries.
^^^this
With or without the plug you need to use a breaker like Wayne posted. You probably already have one mounted somewhere near your batteries. Just make sure that you have the correct size. The reason for the disconnect as Wayne posted and Steez stated is because these new trolling motors can be damaged if left connected while charging the batteries. Both the parts are usually placed in the back near the battery.
It will work going direct to the battery but you are rolling the dice on ruining an expensive trolling motor.