Adding 200 lbs to the rear removes 200 lbs (roughly - not quite exactly, but close enough) from the tongue. You need to maintain 12-15% of the total weight on the tongue. I highly recommend using a tongue scale so that you know what your tongue weight truly is.
https://smile.amazon.com/dp/B007REJTGI
There really aren't a lot of options. You need to restore tongue weight somehow. Sometimes loading differently works. Sometimes not ... If it doesn't, then you'll need to reconsider putting all of the bikes on the rear.
FWIW - my trailer was designed to be towed with a full water tank and the water tank is at the back. I don't do that, so my tongue was overweight. I put bikes on the rear which corrected my overweight tongue.