Artwork to celebrate magazine's 100th issue

I need a designer to create artwork using 100 front covers of my magazine. I am not a designer so I am open to ideas. My thoughts were a straight 10 x 10 or my favourite covers in large as a border and the remaining issue randomly mixed up in the centre. But, as I say, I'm open to suggestions.

I would like the artwork to be either 50cm x 70cm (The frame I'll be using has a mount) or 61cm x 91cm (to be used in frame without mount so would need white border)