I saw that video too and i also have a wii, you can download the emulator also, its pretty cool. I think you still have a way to go. The wii ui is pretty basic so it shouldnt be hard to outdo them.
I think you should change the number of buttons from 9 to 6 that will allow you a lot more room for other controls. I wouldnt stick buttons inbetween bigger buttons like you are now, it just looks like the ui wasnt planned out and your just sticking stuff where you can.
IMO i think you should think about what it is you really want to achieve.
Emulate the wii menu 100% - you'll be stuck trying to adjust the layout to adapt to carpc needs and end up with a bastard version of the wii menu.
Emulate the theme of the wii - here you have the most control as it isnt looked apon as being and exact copy of the wii menu and you have the freedom to change the layout to what you need it to be.
Here is a skin that emulates the theme of the wii menu, but yet doesn't use any actual elements from the wii.
Here are some beta wii menus when it was still called the Nintendo Revolution.
Just posting them cuz i think they are cool and way better looking that what Nintendo actually ended up going with. And they would make some cool skins for RR. Not sure why they went with what they have now if they had way better stuff before. I think the wii menu looks a lot better in those youtube videos than in person. Its just too simple with really no details anywhere, but i think they wanted something a 4ry old could navigate. In that aspect i think they succeeded cuz my 4yr old daughter can get around it with no problems.