Well, there's Maracaibo which I like but one I really like that's closer in is VillaBlanca Wall (where I hit 159 feet). Santa Rosa is a deeper wall dive and Tunich is also. Punta Sur is pretty deep but I'm not sure if I'd call it a wall - more like an enormous coral head but I may be wrong on that one. Deepest I've hit there is about 130 feet.
I just brought up my dive log on my laptop and once I hit 156 feet at Palancar Horseshoe so it's likely a wall.
There are probably many more that I've dived on top of the wall as second dives but I haven't dived them on first dives.
Those are all that I can deduce from laptop as all my old paper log books are in Cozumel. Hope that helps.