We have the GEO-3 plates.
IMO you've got a couple places you could try adjusting
I made my plate in bright mid-day sun 2min @ f/8 and that seemed a bit overexposed. But it was even illumination. So your possibly underexposed.
Gotta get your temps down and keep them reasonably consistent from bath to bath.
Other than that, looking forward to seeing your next try.