The Alliance are able to unlock the void elves (exiled blood elves who can tap into shadow magic, trained by Alleria Windrunner after her experiences on Argus), Lightforged draenei (draenei members of the Army of the Light who fought the Legion on Argus), Dark Iron dwarves (fire-blooded cousins of the in-game dwarves of Ironforge), and Kul Tiran humans (larger, more heavyset versions of the in-game humans of Stormwind).
Finding the best route for you can be a bit tricky because of the size of the dungeon. I will usually only do about half the dungeon, killing as many mobs as I can in 6 minutes. After 5 minutes, make a group in the group finder and leave it. That will leave you a minute to complete your 6 minutes and you will be ported out on the 6 minute mark, ready to reset and port right back in.
The greatest potential for going from 25,000g to the gold cap of 214748g is transferring servers. However, this also presents the greatest risk and needs the most preparation. First off, transferring costs money. If you go to a server, transferring back as soon as the cool down is up is expensive and impractical. You should look for a server that you can stay on for at least 6 months to a year before transferring back with your huge profit. However, the maximum amount of gold that a max character can transfer is only 20,000. Therefore, you need to purchase goods that are going to net you the most profit when you go to sell them on the new server's auction house. Primarily, these are enchanting mats, but can also be BoE epics depending on the two servers. Before making a risky decision such as transferring, consult the questions below.