Hi Pilou
I think your light bulb logo is great. In fact I'm using it myself on my backups dvd case. Definitely think it should read Moi3d - small i and d and the image you've chosen is fine cropped top and bottom. If you got the whole thing to fit there'd be too much surrounding space. On mine I just brightened the yellow to help it stand out a little better against the grey. As it's only really for my own use I hope you don't mind. To be honest I've been really ill the last few months and getting back to doing some 'creative' work has helped no end. Also caught up with leaning how to do much more with Moi :)
Regards
Ron