My favorite part of Postcrossing is choosing postcards to send. For myself, I love the surprise in the mail and the addition to the collection, so I will like any postcard you send!
I hope you will put the date on the postcard. I love seeing pretty/interesting stamps.
If, like me, you enjoy the hunt for the postcard to send, I love (in random order, except for the walruses):
• holiday cards, even if it's not near that holiday
• Inga Paltser
• Atelier Nouvelles Images (http://www.nouvellesimages.com/Postcards_Atelier-Nouvelles-Images_rg~1)
• Inge Löök
• non-English words/poems
• Hello Kitty
• calendars, maps
• politicians and royalty and celebrities
• schools, colleges, universities
• Sometimes people worry when they don't have anything on a list, but the list is just for ideas, for fun. I like surprises too! Something you think is pretty or interesting or fun!