My opinion is of course a personal one gained from my own experiences and I don't expect it to be taken as gospel.
I have built model boats mainly and some model aircraft from scratch for 34 years on and off and liteply is the last medium I would choose with which to build a model boat.
I first came across the stuff when asked to build a high wing trainer model aircraft kit for a friend and lite ply was well suited to that job.
The wood splinters easily and has a soft mushy core.
It absorbs water like a sponge making it heavy unless completely encapsulated in epoxy or some such gubbins.
It is non durable as is the glue that holds it together making it most unsuitable for the marine environment.
If you are putting so much effort into building your pride and joy from scratch, you want it to last a good many years, or I do anyway
Of course we all choose materials to suit budget and the task required of it and I take my hat off to anyone exploring medium choice and new materials.
I just don't like lite ply
for marine purposes.
Its just that by the time you have spent money on gubbins to protect liteply from the elements you might well have chosen a more expensive but more durable material in the first place.