Regular Moria is pretty weak physically for Shishibukai, although his shadow spears are incredibly powerful, and his shadow shields are very useful. What makes him into a wild card is that if he's fighting in sunlight, and simply cuts away someone's shadow they will turn to dust almost immediately; and that if he absorbs several hundred shadows his power and size increases beyond Oz, to the point where he can split an island as large as Thriller Park with one blow. That's a level of raw strength far beyond Luffy, or probably what we've seen from any other One Piece character for that matter, Joz included. Of course, he doesn't actually have 1000 shadows handy without special circumstances, can't hold them for long when attacked, and cutting powerful people's shadows off at normal pretty weak power isn't all that easy... So at regular size he's apparently "only" equal to Whitebeard's 10th commander, whereas Mihawk is apparently a little weaker than #3, and probably a little stronger than #5, and Blackbeard is able to defeat #2 (which isn't the same as being more dangerous than Ace to a non-DF user).
