If, okay again if, the Star Wars line of films are B listers, what pray tell is on your A list?
I definitely like a balance of "Science" and "Fiction" in my Science Fiction. Of course, Im OKay with Creative License (Sure, I can ignore the fact that The Death Star would have had gravitational effects on Yavin and its moons -- that would be NitPicking......but large battlecruisers
on fire in the vacuum of space is where I draw the line...Also, the fact that Ive read Asimov's "Foundation" series and recognize where a bunch of ideas in Star Wars were shamelessly lifted from didnt help its cause with me)...
Its one of the reasons why I read more than watch movies (especially movies based on a great book with the exact same title but the screenplay is only mildly based on characters and plot of the original book)........
As far as movies themselves that I would put on my A-List (not in any order) of Sci Fi that i have not read any associated book, here are several off the top of my head that I can think of (had to Google the years):
"Pi" (1999)
"Soylent Green" (1973)
"The Island" (2005)
"Cube" (1997)
"Silent Running" (1972)
"Exam" (2009)
low budget "Dark Star" (1974) is a guilty pleasure
"Europa Report" (2013) was slow, but good and one of the few "found footage" films i liked
"Inception" (2010)
"Gattaca" (1997)
"Primer" (2004 - imo, best Time Travel movie ever)
"Interstellar" (2014) is a movie I didnt care for plot-wise but the "Science" was good
......