Hi again, Giles, good idea to split up your post into various ones and distribute them into their respective forums, I might as well move one other of your threads that's sitting in General right now over to here.
As to critique, well, the first two look technically correct, very nice subjects, too, well focused, nice colours and adequate contrasts.
The middle two are not quite in focus, they are a bit soft (with macro that should not happen, is my idea of macro photography) and lack in contrasts, too, mostly so that little bug or centipede or whatever that is.
For the last I would wish for some more DOF (depth of field) ... I don't mind that the letters become blurred towards the background, but personally (mind, this is a very subjective thing!) I would have liked to also the see first letter in focus. But that is just me, others might think differently about this.