Yeah, I couldn't agree more!
ALIEN was a horror movie, ALIENS an action movie, ALIEN 3 something of a psychological thriller and ALIEN 4 -- an unsuccessful spin-off of all three (but it has Winona Ryder, oh, come on!?
).
The same thing with the TERMINATOR -- "THE" was more of a horror movie (I remember I was dying of fear when I first saw that scene he picks out his eye), the second one was a pure action flick.
Eventually, I came around to ALIEN 3 -- and it upped from an "average" to "not bad at all" in my books -- it's just a "bit" different. It lacks that genuine horror veil of ALIEN and the fast-paced action footages and cliches of ALIENS, but it still works fine as a "psychological" kinda movie. Or at least it worked a few years ago when I saw it the last time.
The bad thing is, it would retain its meaning with just whatever alien creature in it, not necessarily the Alien.
I place ALIENS in the same category as PREDATOR or RAMBO -- the movies of my childhood. It's difficult to stay objective when you watch them.