Top Contenders

I've been looking for inspiration for the layout of my future I Spy quilt.  Crafterhours has a Pinterest board dedicated to quilt designs and I also googled "charm squares" for additional ideas. 

I like the layout of this one.  It's bright and fun.  I could either cut up the smaller print squares received from the swap for the tiny rectangles or I could use solids/prints already in my stash. 

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This next one is similar to the one above, but it has fewer white sashings between the prints.  The pattern uses 38 charm squares, but I think I'd want a bigger quilt, so maybe I'd need an extra row or two?

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I also like the idea of a color spectrum quilt, such as this one or this one.  For the latter I think I'd need 600 squares.  Bummer.  Maybe this one would also work?  Any other suggestions?