Great pics!
I don't want to detract from your experience - and none of what I say is meant to do so - but I've always found the disconnect between the number of torps required to sink a capital ship and the number for some crappy merchant to be a major issue.
Capital ships had massive buoyancy, dedicated and well-trainined damage control teams, large numbers of pumps and other damage control equipment, large numbers of compartments, torpedo 'bulges', ability to counter-flood etc etc: in other words, they were designed to take quite a bit of damage AND survive it. Most merchants weren't compartmentalised to any great extent, their transverse bulkheads were often weak, they weren't drilled in damage control, nor were they really well equipped for it, yet you can put 2 torps in a large merchant and it mightn't sink immediately, while the same 2 torps sink a capital ship.....NUTS!!!!
Most merchants sank from a single torp, and most within 20 mins of being struck (and often much more quickly). Most light cruisers sunk by torps only took 1 to do so. Most capital ships - especially battleships - were much more difficult to sink. I think the sim does a poor job of handling this difference, although I believe it is largely due to the limitations of how SH3 assigns damage/durability.
Despite all that....great effort (especially surviving the 8hrs DC attacks

).
Just curious - and not implying anything about the effort - what sort of difficulty do you run at? I don't think I'm at a skill level where I'd get shots off at those beasties so effectively!!