You are right. The Great Lakes is something very special indeed. Photographically its a wonderland. I havent had as much fun for a long time. With the zebra mussels being introduced into the lakes a few decades ago it really has cleaned up the viz. All these wrecks we are working on in Presque Isle is in the 45-55m mark. Its pretty cool on the bottom (3ºC) and ascending to 10 meters water warms up to 10ªC and a further five degree increase at the last deco stop (which is very welcoming!) Getting over the colder waters by wearing the proper gear is totally worth the hassle.
The ambient light is lower but water is crystal clear. I have a Nikon D810 and been putting it through its high ISO paces. Just remember that these wrecks are unique. Nowhere else in the world can you dive 158 year old wooden schooners which are sitting bolt upright. They are so intact and pristine all you need to do is bring them to the surface, put sails on them and off you go!!
Here are a few shots. Hope you like them. Of course there are over 6000 wrecks in the Great Lakes and range in all depths from just below the surface to 100m + deep. obviously the deeper ones are more virginal and not effected by damage (but then you have to spend long periods of time decompressing in the cooler waters).
Typo, three masted Schooner 40m (137 foot) built 1873, sank 1899
Kyle Spangler 40m (130 foot) Schooner built 1856, sank 1890