It's me, I didn't explain that very well - it's the elevator that takes you up to the catalyst, just after Anderson dies. Hackett contacts you to let you know that the Crucible has docked but isn't working, and then you try to get to a control panel but collapse. At that point, the Catalyst could literally just let you die.
Tbh the whole Catalyst thing pisses me off - having the main antagonist introduced as a deux ex machina in the last 10 minutes, never my idea of a good ending.
Ah, understood. Yes, I see what you are getting at. My take is a bit different, though I can see how you can look at it a different way.
The Crucible unlocked the Catalyst, basically inserting code into it that allowed the choices before you.
Getting the Crucible to the Citadel was what caused the elevator to come down.
Prior to that, the Intellect/Catalyst was there, but wasn't going to let you in.
There's still all sorts of flaws in that construct though - why the Prothean/Ancient Race crucible required the Leviathan's VI/Intellect/Catalyst in the first place.
Of course, while the Catalyst was the collective consciousness of the Reapers, it wasn't in direct control of them (at least that is my take). Harbinger said they were all distinct intellects in ME2.
Lots of unnecessarily compicated hookum for what could have been a straightforward situation.
I can only really see them going in three directions with this;
1) Prequal - if only to give them more time to ponder what to do with the galaxy post ME3.
2) Far future - Looking at the 3 endings historically through the prism of time, will probably give them the best chance of trying to run with a scenario where parts of all 3 endings play a part.
3) Canonize one ending over the other two
Personally, I think it'll be #3. They'll canonize 'destroy'. In terms of narrative it would have the least impact and give them the best platform to move forward in terms of keeping what they had in ME1-ME3. They'd lose the Geth, and they'd lose EDI, but beyond that, not much difference.
I remember seeing the overwhelming majority of people chose destroy, and it does leave the setting mostly intact.
I still think you need the Reapers to be gone (at least initially - they always make a come back) in the post setting.
If it were me, I'd do more with the reason behind the Reapers because right now it's pretty bogus - other characters investigating the Reaper legacy and how it interacts with the ongoing events. You could do lots with that, and continue to build the story to a more satisfying conclusion.