100mm/-6 on there & 3T Ergo bars which are apparently notorious for being longer reach than stated. Loads of spacers, at a guess 40mm. So 3cm back and 2cm down would be possible, followed by about 1cm back with different bars.
I could also try an 80mm stem, 2cm down and different bars.
I've been using the FSA Orbit or something shallow drop bars for ages. They're cheap and work.
Not sure how they compare to yours but they're much shallower than the previous ergo bend bars I was using. How stretched out are you at the moment? Seems a substantial change. Is it causing problems?
What stem length and angle do you have now? How many spacers are under it, if any?