I think you would do better by fully releasing the downhaul and also (if you didn't do that) completely run out the main traveller even if that means that you have to pull the mainsheet in some. But releasing the downhaul can make a big effect.

Next step would be the power righting methode. In principle you should have to stand on the daggerboard at all with those weights. But the daggerbaord can take pretty big loads, during normal sailing both the daggerboards and wells are subject to about 150 kg sideways loading. They should be able to carry a single person, but I'm still heasitant to stand on them because if you fall of them you can hurt yourself badly.

On monohulls you always stand on the daggerboards when rigthing and although they flex they do take the load.

Wouter