Map
First of all, the angle of the map needs to be corrected. The current in-game map shows the Memorial District in the northern sector, and the Nobles District in the southwestern sector. This is not correct, as if you leave the Memorial District, you are supposed to go straight to the Prison, which is in the northeast. The map currently suggests that the Prison gate goes northwards, which would put you in the middle of that north-south exterior wall, not at the Prison.
To correct this, the map needs to be rotated 30 degrees clockwise, so the Memorial District is in the northeastern sector, and the Nobles district is in the Western sector. This applies to both the "Imperial City" area map and the "Cyrodiil" zone map with IC in the middle. Below is an example of what the centre of the "Cyrodiil" zone map currently looks like (top) and should look like (bottom).


Notice how the Memorial District door and the interior walls line up more logically with the Prison District and the exterior walls in this map.
POIs
I think it's great that you can get Discovery XP from almost everything in the City, and they all get marked on the map and compass. However, there are a couple of strange situations:
- I got both Discovery XP and Completion XP for one of the "Striking Locales" in the Sewers - these types of locations have never provided Completion XP before, so I'm not sure if that's intended. I haven't yet found any other sewer Locales to compare with.
- I got Discovery XP for both sides of the door between the Sewer Hub and DC3, but only for one side of the door between DC1 and DC2, and the door between DC2 and DC3. These should be consistent, and either provide XP for both sides all the time, or XP for one side all the time.
- I found an unmarked door to "Ancient Underground", which was locked. Presumably once I have explored further this will make more sense.
Icons
Currently, bosses in the Sewers are marked with the Battlefield Quest Hub icon:

. I think it would be a clearer indication of what the POI contains if they used the same icon that Group Bosses in the Overworld use:

.
The Districts are currently marked using the Town Quest Hub icon:

. Considering there was UI art made especially for them, they should really be using the Imperial District icon:

. Hopefully there already exists an "incomplete" black version of this so that it would function in the same way as the current icons; if not, all you need to do is invert this white one

.
The sewer entrance icons seem to have a representation of the Dragon on them, but during the Second Era, the Dragon is not part of the Imperial emblem:
link.
Unmarked Objectives
Centre-screen Objectives pop up when you enter certain parts of the Sewers, but there doesn't seem to be any related map marker or quest objective, so I'm not sure what they are actually for. Some indication of their purpose would be useful.
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