Not great, not terrible

[My reviews are based on a mixture of subjective preference and objective game design criteria]

Design ratings:
-Originality: 6/10
-Aesthetics: N/A
-Thematic Consistency: 8/10
-Custom Content: 5/10
-Grind: Low

I tried this out while on my search for an ocean based modpack. The hint of a story intrigued me. There is no story, however, beyond a couple questbook notes. I also didn't find any structures in the ocean, though I admittedly didn't look very far.
I played for a couple hours but ultimately decided to drop the pack. I checked better questing in edit mode, and the questbook is essentially a collection of "craft this" quests. There are also very few recipe edits (a single script with half a dozen lines that integrate some magic mod items into the tech recipes).
The setting is somewhat interesting, with the entire world being under water, and the player starting in a custom structure. But the pack doesn't really seem to go anywhere with further custom content beyond that. It might be fun for players looking for a light pack who are new to custom starts and unfamiliar with the mods used, but I otherwise can't recommend it.