The one seemingly straight rail on top of ramp is actually slightly sloped (the slope begins halfway that rail piece).
So a solution could be to not allow curved rails directly on top of rail support, only two straight rails.
(I doubt this is what you envisioned your suggestion would lead to ...

TL;DR
Allow rail ramps to curve 1 rail earlier

What?
The top of a ramp looks identical to a rail support, but the support can begin a turn 1 rail earlier.
Screenshot 2025-02-13 142335.png

I suggest allowing the curve to begin at the same location as it can on the support. There is 1 straight ...

+1
For anyone looking for advanced platform logistics in the meantime, consider using token items as described here https://youtu.be/hM-fR2_N3Mw
It's impressive how creative ideas can overcome limitations like this, but unfortunate that it's so hard to compensate for the lack of a feature that would ...