Last week I mentioned how Shattrah City is the home of the Refugees of Outlands...well Lower City is the REPUTATION of those refugees. Located in the lower most portion of Shattrah , Lower City is actually the outer band and it is here where players will locate the majority of the trainers, vendors, battlemasters, etc.
The largest population of these refugees visually in this area is made up by the Arakkoa or "Bird People". If you are serious about getting this reputation to exalted the best thing you can do before doing ANY other quests that give Lower City Rep is pick up The Outcast's Plight from Vekax. (He is one of the Bird men who that pats up and down the ramps in the Tree house located at the North End of Shattrah.) This will open up a repeatable quest for 30 Arakkoa Feathers which can be done until you reach Honored. These feathers are NOT soul bound so they CAN be purchased off the Auction house or easily farmed.
Once you have reached Honored pick up your heroic key from Nakodu because there are only two options available to you. Quests and Dungeons. While you will find quests for Lower City, there are not many (only 59) and some are seasonal. Others are only occasionally available, and some are faction specific. This means that the MAJORITY of your reputation will have to be obtained in dungeons. Specifically within the Auchenai Crypts, Sethekk Halls and Shadow Labyrinth. Crypts will only give you rep while on Heroic mode after you are honored but Sethekk and Shadow Lab will give rep on both normal AND heroic. Your BEST bet will actually be finding runs for Heroic Sethekk Halls with individuals who are farming Anzu for the mount if you are not level 80 yet.
For those who ARE level 80 and reasonably geared out (with the new system something that is VERY easy to do.) I doubt you would find it difficult to solo Sethekk Halls, even Shadow Labyrinth should be doable if for nothing more than all the trash mobs.
The Mythic Roadblock
3 days ago