The Dark Depths combo is by no means a staple in Maverick. The combo (Thespian’s Stage & Dark Depths) can be a great way to ‘get a win out of nowhere’ but also puts pressure on your mana base. Although Dark Depths should never be considered a part of your mana base and should be considered a spell, having either of these cards in your opening hand can be a little awkward from a mana perspective. However if you’re also running any amount of Crop Rotation, having 1 piece online early can find you wins out of nowhere.
My local meta has a huge amount of Karakas, Swords to Plowshares, Baleful Strix and Diabolic Edict type effects so I haven’t been on the Dark Depths plan for a while but can see it being played in a GW-based deck. I believe it’s a little greedy to play the combo within a 3-colour version of the deck but I have seen success with it before.