Like you, I am a huge Alien franchise fan, and although I have my favourites, I haven't been disappointed by one... until Romulus.
'Alien: Romulus' was inarguably, for me, the worst in the Alien ennealogy. I gave it 4 out of 10.
The characters were WAY too young - maybe they were targeting a youth audience, forgetting that some of us have been watching since 1979.
I didn’t see any fresh twists, and there was not one likeable character, or… not even not likeable, but just interesting... even UNlikeable.
I have watched the other seven from three to eight times each; I won’t be giving this one another run. It was, sadly, just lacking ANY redeeming features, and there were too many cringe moments - "Get away from her, you bitch" - seriously?