This has been a perfect application for decopatch. The red floral design I chose in the end has covered up all the scratches and scuffs nicely. The glossy glue has given it a nice protective sheen which will cope with new knocks and scuffs well I am sure. In fact it looks like it was manufactured this way now!
I haven't got enough of the red decopatch paper to do anymore covering up (and the remainder of the case would be a bit fiddly anyway) but I think it needs a nifty luggage tag or something to finish it off. Maybe even a crochet flower charm (I know I'm not a flower person but I could bend the rules a bit here!)
It turns out that *E's* blue version is exactly the same size, not bigger as I originally thought. If my children were 5 and 8 all over again they could have had one each (the blue one with a geometric boy design of course).
Maybe one day I'll have grandchildren! 'Ugh No!' says *E*!