Geometry of Look-Back -- lensing

Pursuant to an old thread, I wonder who can answer this:

Let's pretend for a moment that there is no dark matter, but that the
gravitational lensing that we see happening out there is affected as
follows:

(1) The lens / target are at different distances than we suppose, and

(2) There is a migrating universal "constant" such that in earlier
epochs matter bent light more per kg than it does today. In other
words, lensing effectiveness is proportional to 1+z, or maybe the
square root of 1+z.

For (1), my question is, if we alter the distances to lens and target,
even if very unreasonably so, can we recover the lensing that we see?
Or is the only working solution to make the lens much larger & further
away? A smaller closer lens can't bend the light that much, is that
right?

For (2), my question is, is there broadly a redshift dependency in
lens power, that is, lens mass? Are high-z lenses seen to be more
powerful than low-z lenses, or is that susceptible to a Malmquist
bias?

A while ago I speculated that time dilation might go as the square
root of 1+z instead of the standard 1+z. This is because if there is
a migrating universal constant which operated on the space-time
manifold, then redshift would be half time dilation and half spatial
lengthening. In other words, the past would look bigger but this
self-corrects via Riemannian geometry. I'm wondering how this would
affect the lensing that we see, thus these questions. Appreciate any
help.

cheers, Eric