Hard to beat!

The closest thing for the hatch clamps might be O scale c-clamps.  

I have not heard of a laker going down in decdes. The Fitz is the last I remember.

The newer ones are so high I imagine it is hard for much water to wash over the deck even in a Great Lakes storm.

Yeah; I know this too.

     BUT, and I use this as well. Have you seen or does anyone remember the Gorgeous Little Liners( Ferryboats) that plied the lakes up till the late 50s? They were certainly unique and I thought some were downright beautiful. The one that sticks in my Mind is the M.V. Canadiana. She and I became quite close over the years.

      First, when I was just a Wee Lad, Grandmama wanted to cross Erie to go to Crystal Beach, Ontario.( it was started as a religeous retreat I think). So down to the docks, Tickets in hand we board this Monstrous( To Me! Ocean Liner). Not so, but what did I know? Glass panels to allow the adventurous children a place to go, inside the ship, to watch all the shiny moving things in the Engine Room!

        There were many of these hardy vessels and some have been done as model Kits in wood. But surprisingly NONE have ever been represented in Plastic. Except that Meng Kit and she was modified for ocean travel so to me although Fascinating, As a kit, she is pricey and outside my regular Budget. And no, she doesn't represent what I am referring to.

 I can't scratch build everything for sure. I would Jump on a plastic version of say the "Mt.Washington" or " City of Buffalo " in 1/35 for instance and hang the cost. They just look so unique!

Tanker-Builder

Why haven't they changed this after all these years?

All ship design is a compromise  A running balance of competing imperatives.

So, "enough" is often a hobgoblin.  

One thing is the actual frequency of major storms.  And that, versus the fact that the Soo Locks cose for about three months ending in April when the lake ice finally starts breaking up.

Aother issue is in navigation--the ships have to fit things like locks and under lift bridges and like, adnd not be deeper than dredged channels, too.

The bulk freighters need to stow "hard" cargo like rock ore and iron pellets.  And they have to be "fast" enough to control labor costs, while at the same time not having high fuel costs (or cargo space reduction for bunker tankage).

There's a reason there are only 13 "thousand footers" on the Lakes.

That is a great question. I dont have any answers for you. Sorry.