Can´t speak much for the more tecnical part of DM gametype.
But from an designer´s perspective I really like your map. Loved the architecture and the general theme of the map.
My feedback would be that you could explore more from the water part as well as the outside circle, it looks like it is limited to just 2 types of combat trough out all the map (1 being the chalange fighting underwater). Very nice artistic and practical detail in the well, all those decorations and the health vials are a sure lure in to heal and hide.