Making up a new type of creature that "was there the whole time but nobody saw it" is about as contrived as you can get.
It's no more contrived than the Queen Alien.
How, exactly? Damage to the cryo-chambers probably would wake people up, meaning you couldn't just blow air out without killing them.
You know, I should just put up the dictionary definition of "contrived" here, because at this point you're basically making my argument for me.
Is it so hard to believe that a damaged EEV would home in on the nearest recognizable beacon? Sounds pretty reasonable. More reasonable than no one finding the Derelict in all those years even though the planetoid was only 1200KM in diameter.
OK, I may actually have to put up the definition of "contrived" after all since you don't seem to know what it means.
A contrivance is when something is made up purely to serve the plot and not a natural outgrowth of the story, characters and situations already established. To give an example: just about everything that happens in 'Star Trek Nemesis' is pure contrivance. Randomly detecting B-4 on some distant world from Earth orbit? Using a buggy to go pick the bits up? Getting into a fight with nameless goons for no good reason? All of these are plot contrivances because they have nothing to do with anything that's going on other than where the writer wants the plot to go.
So no, the Queen wasn't a contrivance, it was a natural outgrowth of the Beast's concept from the first movie, answering the obvious question: "where did all those eggs come from?"
Just saying "it's because it's a superfacehugger" isn't a satisfactory answer in 'Alien 3' because 1) no such distinction is established in any cut of the movie I've seen. 2) we are meant to simply accept that an egg got onboard *somehow* without explanation despite the face queen clearly wasn't shown to be carrying one while chasing Ripley and having severed itself from the ovipositor, which is rather essential to egg laying by sheer definition.
There's an egg there *because the plot needs one to be there* and no other reason. That makes it contrived and it's amateurish, lazy writing to boot.
As for the derelict: the only way the Nostromo crew found it at all was because of it's beacon, which in the intervening decades ceased to function. Remember even Newt's family who had an exact set of co-ordinates to go by didn't see the thing until they were right on top of it. Granted, the state of the beacon is not directly addressed in the second movie, but in the special edition it's clear the ship has been damaged by nearby lava flows, so it's consistent. As is the company's incredulity at Ripley's story because of course, they have people on the planet already who would have detected the beacon on day one. We know Ripley was telling the truth, therefore the beacon must have stopped transmitting before the colonists arrived. QED.
People who like movies about swarms of vicious monsters that killed 60-70 families, including children don't like films where children get killed? You logic is not like our Earth logic.
Those deaths were mainly off-screen, and we saw no kids dying on-screen. That makes all the difference to moviegoers.
That's why everyone cheered for Ripley to go back into the Hive to get Newt when before no one cared that she abandoned the Marines earlier. Because a kid dying on-screen is a no-no compared to adults getting killed or abandoned.
Newt was also killed off-screen, so your logic simply doesn't track.
Honestly I'm not sure why you're reaching so much to defend this movie's script. It's well documented just how much of a confused mess the development process was and the manuscript itself was a rushed mish-mash of several *radically* different concepts pulled from previous drafts, none of which were particularly good to begin with. The whole thing was stitched together on the fly by a couple of the producers in a desperate attempt to get *something* out the door. Trust me, plot contrivances are the least of it's problems and I don't think the FOUR people credited with writing the thing would put up as much effort in it's defence.