I like postcards that have some personality. In general I love funky pictures, that show a bit cultural diversity, also allkind of maps. And cards that have the place name written on it. Also i´m quite keen on humorous, vintage and quotation cards. And I if you can´t find anything in that criteria I would also love cards with penquins.
And on your card I would love, if you could write a quotation or a wish in your language. :)
Looking forward to some lovely cards!