The biggest fun of the project was that I was completely free to design the system from the ground up (except the canvas drawing functions).
Regarding the amount of work I have to be strategical.
I try to concentrate on a relatively small core system: get the philosophy right, tune the performance as much as possible. The components which are 'ready' right now: Window, Button, ScrollBar, ScrollPanel, GridPanel, TextEditor, StaticDoc. (StaticDoc is a read-only RichText component, kind of the original HTML.)
The other absolute necessary things needed in the near future: TabPanel, DataTable, CheckBox, ComboBox.
To go further I will certainly need outside help (either other programmers or funding or third party component creators). I cannot create a huge component lib myself. But 10 people can do lots of things I think.