Image #1: Minor issue, in that the torches could stand for a cover to protect them from rain and dew falling from the leaves above.
Images #2 and #3: I addressed an issue previously pretaining to these images. The jutting spires of stone are not aesthetically pleasing, especially the sharper specimens. Nor are they appropriate to a volcanic
caldera.
Image #4: Very unpleasant to view, though it has some potential and can be greatly improved upon.
- There is a complete absence of shallow water which typically surrounds
atolls. The images displayed at the link should provide you with some inspiration on how to fix this issue.
- The nature of the distant landmass is unclear. Is it the very tip of a peninsula? An island developed from continuing volcanic activity? Or a dormant volcanic island? The barren theme of the landscape causes me to conclude the island is somewhere between the latter two states. But the terrain features lend to the ambiguity. The tops of the natural rises are pointed, while the slopes are smooth, and altogether the mass is unpolished and undetailed -- save for a few tall & ugly trees. Draw attention away from those desolate trunks with appropriate flora.
- This may also benefit from the previous link to images of calderas.
+rep