Nuke your fresh flowers in the microwave to get instant pressed flowers. If you need to press a lot of flowers in a short period, time may not be on your side. Microwave pressed flowers are quick, easy and equally beautiful.
Flowers or feathers would look amazing. maybe next year's apple blossoms! Do multiple of these then frame as if the were window panes. Place a large old frame (outside frame only) around it to form a faux window.