I must admit I am not sure I completely understood you here, so did you suggest reducing the attractiveness of the Space Elevator in order to allow for more custom buildings, until the bug has been found? So, the Space Elevator must have an attractiveness of at least 535, probably more. I guess it's done to simulate pedestrian traffic in and out of the building. Many vanilla unique buildings have attractiveness values of 5 (not a typo), and Stadium and Theater of Wonders top the list of known values in the wiki with 20. That is often two orders of magnitude lower than the Space Elevator. So, in principle, your suggestion would work.
I guess my personal solution will be different. Up to now, I had the policy to not use any monuments in my city other than the Space Elevator and the Fusion Power Plant, because the others do things I don't want (I put them in my uploaded test city only because I had to remove dozens of custom assets, and I wanted to prevent the city from collapsing). Which means, I'll just put the Space Elevator on the list of monuments that do things I don't want for the moment. My other test city has no monuments at all, so no big deal.
There's also the issue with quite a few custom buildings. Pretty much all of them have attractiveness values that are higher than those of vanilla buildings, although most modders only use very small increases. As higher attractiveness means more visible visitors, some modders use attractiveness values in the hundreds (a few custom casinos come to mind, also some supermarkets I tried) to make the lots look less deserted, which will of course replicate the issue with the Space Elevator.