That seems accurate. Ornithopods are on average quite heavier that theropods of the same size, specially iguanodontids and duckbills. And the later could get really, really big...
Now I´m regretting making this guy so "gracile". Probably the limbs should look like a more robust morph of I. Bernissartensis, with broader metatarsals and forearms...maybe in the colored version I´ll fix this...