Hi Carlo (and Nicole),
Thank you too for your feedback!
I thought you said you had most trouble finding your angle on the Mercado Central? It doesn't look like that from your images

Some feedback:
LR4-1: Fish Pano
Like the “flow” of the fish. Perhaps darken (“burn”) the fish on the right side of the image a bit as they are now a lot brighter than the ones on the left.
LR4-2: Fish group with crabs
Just a bit too “complex” for my taste (and I think I would have preferred the eyes of the fish to be in focus).
LR4-3: Fish detail
This one is much nicer! I would only fix a couple of details here; the small patch of green at the bottom and the fish blocking the left bottom corner (perhaps simply crop to get rid of them).
LR4-4: Fish in an oval
Good find to use a vignette to cover the edges and get focus on the centre of the image. Perhaps (if there is still room to do so) move the vignette more to the bottom and left as this will get rid of more of the price tags and salmon (which because of its colour doesn't fit in as well as the rest).
Thank you for posting!