I'm really big on matching things (even clothing, furnishing etc). When I find a chart that inspires me I look for matching or complimentary design and envisage where I'll place them in my house.
By planning things out like this you rarely need to re-hang or move the framed design around.
It also keeps you motivated to finish the "sets" as you can see the result in your head.
Sometimes you can get pre-matched designs - like the Queens or the wild animals book.
All in all I find this gives any wall or room a unifying and calming effect.