Moria may not be one of the strongest Shichibukai, but I don't think any of them should be discounted as weak. Just look at what Moria did to Oars, and imagine what Moria could do if he somehow gets Oar's corpse working in this battle. Plus, Luffy has beaten Crocodile before, but that doesn't make Crocodile any less of a beast. Although I will admit, Moria probably is the "weakest" Shichibukai right now.