Memes, properly, are ideas or concepts. Internet “memes” are, um, running jokes I think. Or something.
Tropes are tropes. Also elements, tendencies, repeated themes, motifs, etc. I think the common word when I was a kid was motif.
Fad?
Stereotype, fad, craze, chestnut, pattern, theme… I think trope and meme were necessary to provide specific words for the modern world of mass communication.
Per previous posters:
Fad to my mind has more of a suggestion of short-lived fashion for some concrete object. Macrame wall hangings or geometric curve string art were fads.
(What were those things called? Dark painted board, little nails, bright coloured strings making geometric curves…)
Craze suggests juvenile enthusiasm. Beyblades are currently a craze amongst children of my son’s age hereabouts… just as they were about 10 years ago. 
And just as they were many years earlier when they were just “tops”.
Pet rocks were arguably either a fad or a craze.
Archetype/trope and Myth/meme. Source and manifestation? Seed and propagated virus?
Meh, that’s become a trope.
To some extent “Faxlore” has a similar pedigree. Amusing images and titles which were propagated from office to office via the fax machine.
I’d just like to say thanks for the thread! This shit really bugs me!
The first rule of meme club is …
“It is a truth universally acknowledged. . ."
nm. Ninja’d by kayaker.
OK…wait…how about this:
That’s the beauty of it!
“Germ of an idea”?
As JRDelirious points out, “trope” is indeed an old, long-lasting term that just recently returned to the general lexicon (likely thanks to TVTropes). Your distaste for it is unfounded.
“Meme” is a bit more recent, but the usage for “internet meme” (i.e., a picture, often with text, which goes viral or gets repeated with new text, etc.) is basically a different use of the original term which has overtaken the original meaning.