Greetings!
If you look at the current version of this map you can also see that there is kinda symmetry. Also yes, reworked map is more symmetrical now, but not mirrored ;) It helps to provide more equal opportunities for both teams, but not making the map too boring visually.
But main reason, why this map was changed - to improve gameplay for different ships. Current version has too many islands, what makes it difficult to maneuver. Also these islands are too high and wide, so if you don't have enemies on your flank - you have to make a huge detour for having possibility to shoot. And since this map is used for mid-tier battles, just imagine how boring it was sometimes to play on the Colorado D:
Reworked version got not only changes for islands location, but also a change in the heights of the islands, what should help to support your team.