I think you have done quite well!
There are only `normal' Singapore markings (decals) in 1/200 and 1/144 as far as I know. You might want to try a group I moderate:
http://groups.yahoo.com/group/airlinermodelling
and see if someone else is interested.
So that I don't appeear to be in advertising mode: normally, I would have e-mailed that link privately
There are ways of printing your own decals, though of course you need the art work to start with.