having two bathrooms added above a finished space downstairs and having to put all these drains down to the basement is not a easy task. This is the only area that I have to work with.
And that is why we normally don't do our plumbing in a location like yours.
Normally, it would have been below the floor structure in places and the ceiling would have been boxed out for it.
We can't cut out the flooring system to put our plumbing in.
The framers have framing axes and nail guns. It's not even a fair fight.
At this point, would say, replace the floor joists now, or at least sister new ones alongside all the way out.
I would locate the main 3" run below the flooring joists knowing you are going to box that in.
A vent rises above the pipe at the point of take off. Many of your vents could have taken off under the wall above. That would have kept them vertical.
We can't tell where the wall is below all of that. Knowing the complete layout down to foundation helps us.
We always need to consider structure. Then we fit our work around and through, "only" if it stays structural.