For starters, I want to say that You really show talent and a kind of attention to detail, so I hope You won't be discouraged by what I'm going to write.
But there ARE issues there.
One, I should have mentioned earlier, is that they are not on standard templates. There's no allowance for posting stuff on template that's less than 1000 x 330 for ships shown without below-the-waterline-part of the hull or 1000 x 385 for ships shown with the underwater hull.
Templates can be found on Shipbucket Wiki or in the dedicated thread (they were all watermarked, but just added 'clear' copies a moment ago):
viewtopic.php?f=5&p=195610#p195610
More importantly - there are still double black lines and heavy corners. And lots of them.
Under no circumstances whatsoever use the same "black" for "contour" and for "paint".
If something ends up being 2-pixels wide, then (with an exception of barrels of 3-inch guns) don't make it 2-pixel-wide-black.
Either make it 1-pixel thick, or make it 3-pixel thick (black-color-black) or (
very occasionaly, just in some circumstances) 1-pixel-black + 1-pixel-dark-grey (or whatever color that thing is). And generally - if it's something on which a person is supposed to walk on - it should be 3-pixel-thick. (also, if the thing in question is getting narrower along it's length, then sometimes a viable option could be making it 3-pixel thick for some of the length, then 2-pixel for some length and 1-pixel at the tip, but I would be generally very wary of relying too much on that technique)
As for various kind of antennas and similar things (but also grills etc.) - I suggest using a non-black color (dark grey or whatever is appropriate for a given element). It seems that a numbr of elements You just represented without attempting to find some way to understand their actual shape.
If these tiny 3x3 dark grey crosses on the Pr.503 hull are portholes - they should have blue dot in the middle. And if that yellow thing on bow is anchor, it also needs black outline - so does the bottom of the motor boat.
(on the other hand - that yellow mast over Pr.864's bridge is one place where I would perhaps leave it non-outlined, but make the shade darker. (but that's just my way of showing things that are not-black-outlined they are of "solid contour")
I added a sample of one detail of Pr.503 that IMHO could be done more neatly, as an example You could, perhaps, take for considerations when drawings similar elements.
Ah, one more thing - You have artifacts over the bridge of Pr.503 (around lines/antennas etc.)
Marked most eye-catching examples, but don't take it as an exhaustive: