Have you thought about fitting a back rest to your existing console? With a bit of a bend in it (rearwards) you might seat two people especially if they are good friends. But even if this does not work it would make it more comfortable for you.
You should try a boat with a bench seat before splashing all this cash, in my experience they are uncomfortable, wet and although a good place to store things take up a lot of room. I am now going to hide for a bit because I know the med crowd won’t agree.