I do actually like the current demo you have put up here. May be the animation can be made little more soothening to the eyes to avoid eye strain by avoiding frequent rapid movements. I liked the current demo with zoomin storyview, but the downside is that I have to close all the opened tiddlers to go back to the landing page. This can be avoided by providing a quick access button to the landing page on top of all tiddlers or somewhere else.
Or may be you can revive the cecily storyview for TW5 - Project Cecily - a zooming user interface for TiddlyWiki
Then choose two palettes (one dark and light palette) that work well with the landing page and documentation site and provide a button to switch the palette easily.
And finally use more images with only relevant text to convey the matter in the landing page like in bottom part of the Memory Keeper homepage - The Memory Keeper - A Personal Research Tool — v1.0.04 Adventures in Genealogy Research
Also the mobile view needs some minor fixes. Mobile view works best with zoomin or pop up story views.
That should be enough. I checked website of many other note taking apps. Almost all of them have a similar pattern with a topbar having links to the contents within the the homepage.
Below given are two examples.