Check the discs for run out
That's where I would start. I often check runout when installing new rotors. Check both sides (inboard and outboard) of each rotor, note any high and low spots. For specs, see attached .pdf.
If you get numbers out of spec, remove the rotor and re-mount it on the hub (e.g., 180deg) and measure again.
As usual, make sure the hub surfaces are smooth / clean, ditto for the hat in the rotor. Any rust should be removed (I use either a needle scaler, or a chisel with just enough tap from a hammer to knock the rust off).
Check the brake rotor thickness as well (see attached). Even a few thousandths variation in thickness can cause a LOT of pulsation.
Check your hubs for runout as well, as bearing wear may allow the hubs (and thus rotors) to run askew, even if the rotors are true.
Make sure the pistons move in/out smoothly in the caliper bore w/o bind, so that a pad / the pads aren't dragging on the rotor.
I can't help but wonder if bad ball joints / tie rods / worn rubber bushings might allow play in the front suspension that might manifest as a pulsation or wobble during braking. Hopefully others will comment.