Some general personal advice to players which is mostly from personal play and is considered opinion.
If you have the expansion pack the Huns are generally considered to be the better "Horse Archer Rushers". They get some nice discounts on horse archers and a much better unqiue unit (imo).
While I've always enjoyed horse archers I find that the Castle Age restriction affects them gravely. One should really be raiding in the Fedual Age with infantry rather than focusing all efforts on trying to reach to reach the Castle Age and focusing on rather expensive horse archers.
The Japanese are a nice infantry focused civ which get nice economic bonuses like faster fishing ship food gathering. They're perfect for a jack-of-all-trades focusing on early rushing and expanding industry.
I've always prefered the Britons when I'm trying to footman archer rush. They get range bonuses depending on age. Which is, to me, the most important aspect of archers. Archer raiding civs are great against "turtling" players since you can often pick off lone villagers without having to reveal the raiding party like infantry heavy civs.
If you're one of the "Defensive players" consider the civs such as the Koreans, Byzatinium and the Teutons. If you set the age limit to Castle you'll find that the defensive civs are much much stronger and only real dedication will crack your defences. Which will allow you to focus on a counter offense.
The civs could really be split into low, medium and high tech. The Goths, Aztec and Celts for example are considered low tech and are generally good for rushing. The Britons, Franks and friends are considered medium tech. The Spanish, Turks and Byzantium are considered high tech which are better in the later ages. Use this to your advantage when the host changes the starting age, or your own personal playing style.