themeing has a lot to do with it, themeing can take a little 100 ft drop woodie and make it awsome. but if u dont' want to theme then u just build what hasn't been built like MF
TOGO fan, you would loooooooooooovvvvvvvveeeee Ultra Twister @ SFAW! It is the roughest coaster ever.
For a steel coaster it is speed airtime and insane drops and turns
for wood it is also speed airtime and good drops and turns but a woodie also needs some good theming and "the head chopping effect"
an inverted coaster needs goodspeed and some nasty inversions in a sequence that will totally confuse your mind.