There is no denying about that. I have an explorer and datejust. But their glacier evolution of styling and similar case between models are nothing excited in terms of design.
Oyster perpetual is a date-less and cyclop-less datejust with brushed lugs and some fluted bezel.
Explorer is an oyster perpetual with different numbers and hands.
Air king is an explorer with diferent dial and size.
Submariner is a GMT with brushed lugs and diving bezel.
There is not enough diversification their models that makes them an interesting one-brand collection.
Of course, this is just my personal opinion.
Your collection is very interesting.