What are the most overused topics and or plots in sci fi fantasy novels?
Alien menace invasions ( War of worlds, etc)-pro-violence, The idea of advanced, civilized but miniature and microscopic aliens-For some reason very popular in the fifties despite near-impossibility of intelligent llife existing in the size of say, HO railroad cars, etc.There were a number of short stories-on this theme adapted to radio drama-far easier than to tv. the size differential that the aliens and their crat were miniature, was sort of a (easy landing) answer to the problem, I am not aware of any UFOs that are miniature sized- unless these are unmanned spy or scout stellite probes as we have for weather and other purposes- communications satellites, spy sats, etc. drones/ There are some intriguing social content themes that are neglected in sci-fi they are controversial- benign captivity versus freedom , for example which was central, or rather off-center in (Captain Nemo and the Underwater city which should have been updated to say Commodore Wushneva dn the secret sub base! Base was in the Pacific and if updated , maybe the Russians had something like this and killed any accidental discoverers! It"s aBig world-universe. that"s my take.