Snorlax can be a good option. My main problem with using Assualt vest though is that I'll lose access to rest, leftovers and curse, moves that in the past were pretty essential to it. Plus its SP.Def is good enough I thing to afford not running that item. Still, it might be worth considering.
Don't like Goodra too much. If I were to go with dragon I'd go with Dragalge.
It has a good enough movset to go all physical. But I don't know how much it will really benefit from Assault vest, considering it's HP and SP.Def are not really that high. For example not only does Tyranitar have higher health and the same SP.def, it's ability Sandstream boosts its SP.Def even further. As long as Sand Stream is running Tyranitar has the same SP.Def as Goodra.