I'll be very happy with all postcards I receive, but if you want some suggestions for the kinds of things I might particularly appreciate...
I like small museums and art galleries,
paintings and sculptures,
ice cream and chocolate,
snow and ice and Autumn colours,
train travel (especially on long routes across continents),
books and reading (everything from fiction to popular science, although I don't understand much of the science),
languages and words,
photography (from its origins to modern-day),
stamps and letter-writing and envelopes and postboxes (of course!),
cities (especially, but not only, if they have a tramway or a river running through them),
opera and contemporary dance (in both cases, watching not doing!!),
cinema (outdoor, indoor, old, new, English-language, non-English language, comedy, drama, animation...)
any, many other things (including lists!!) but these really are only suggestions. I have been happy with every card I've received so far and have no doubt that will continue to be the case.
I also collect stamps so, if it doesn't cost you more, if you want to send cards in envelopes so I can also keep the stamps without breaking the postcards, that would be great!
Many thanks and Happy Postcrossing,