I suspect a lot more would change for this LPD version to really work. The underwater hull would likely change shape somewhat, to create space for the dock and the ballast tanks attached to them. Those ballast tanks also need venting, which should come up somewhere on your decks, so while that would not have a huge impact on your design, it will mean the level below the helicopter deck will have a different arrangement then the JSS.

I am also not sure what the impact of that huge superstructure expansion will be on the ships stability, I personally would expand only the hangar and maybe one deck above it. That also limits issues with the horizon view of the aft radars from the I-mast.
Still, interesting idea, just needs a bit more work

Original design JSS had a deck higher than it is now.
Hence the I mast standing on a "foot" so the seastar and smile can look over the funnels.

The current JSS is also heavy in the bottom making her unstable in seas by pulling herself upright swift and quick.