The eMTB world has gotten craaazy good. I would look into that market if concerned about weight and ease of getting in and out of a boat. Many of them are lighter than most of the standard models I see guys using for hunting bikes. Down side is cost and they are pedal assist only ( if looking for one with a throttle, most of them are not setup to run that way).
Research components more than brands IMO. Its been mentioned nearly all the major players are using the same components and simply building ( or branding ) frames. However not all component levels are the same so make sure your comparing apples to apples when looking at price.
If using it in any kind of hilly terrrain, or putting any load on it do not waste your time or money on anything other than a mid drive.