Some unpopular opinions here but I think these sequels were better than originals:
Rambo II
Aliens
T2 Judgement day
Ghostbusters 2
The dark knight
Evil dead 2
Kung-fu panda 3
A nightmare on elm street dream warriors
Indiana jones and the temple of doom
Spider-Man 2
The Road Warrior/Fury Road
Blade II
Star Trek II: The Wrath of Khan
The Empire Strikes Back
X2
New Nightmare
Star Trek Beyond
The Color of Money
Any Mission Impossible movie from 4 onward
i definitely prefer alien, evil dead & terminator over their later films.
but i'm with you on dream warriors. i watched the first three nightmare films last week, and i liked the all quite a bit, but dream warriors is by far the best in my books.
if we can choose any film in a series, then i'll go wtih:
fury road
paddington 2
three colors: red
blade runner 2049
spider-man 2
i also wanna name-check mission impossible fallout, cuz i think that's an insanely great crowd-pleasing action film, but i've barely seen any of the other films in the series & am no judge of which one's the best.
i've seen 3 & ghost protocol, it turns out - i had to go to letterboxd to check, because i swear i can't remember anything about them. that may just be my bad memory & no reflection on the movies.