My approach (to skills anyway) is just mash buttons. I don't know how you melee types manage, but may two mains are Hunter and Lore-master and having long range attacks is the best. I liken it to a dog-fight simulator, try to get behind your enemy using the min-map radar. Half the time I do not even see or know which direction the enemy is, mash the button to fire and the avatar completes the action if possible.
I use a light bridle on my Lore-master and a medium on my Hunter. Pretty much a haphazard choice. You then fill out the traits corresponding to the bridle in your mounted combat menu (or so I gather). You get three (color) choice trees to fill up. With 77 'points' in my maxxed out steed you can fill out one completely and half of a second. The main skills I have unlocked are the pet for the Lore-master and the trap for the Hinter, but other than being very cool to have a pet (not sure how much damage it inflicts), I have yet to figure out what the trap is supposed to do.
I suppose they had some sort of strategy in mind for each classes' mounted skill set, but I usually just pop things as they come available.
Mounted combat as it is in the game right now, is a very dubious exercise. About the only thing I like is that you can destroy unmounted enemies easily or run off aggro quickly if need be.
Right now, it is poorly implemented, but I give em a solid B+ for effort. It is/was a daunting thing to undertake.
[COLOR=#ffff00]''[I]A man[/I] of rare [I]perception[/I]. In fact [he] had such rare [I]perceptions[/I] they amounted to hallucinations.'' [I]Walt Kelly
Dottiel,[/COLOR][COLOR=#faebd7] Kinship(s): [/COLOR][COLOR=#00ff00]There is no Fifth Star[/COLOR][COLOR=#faebd7] (Meneldor)[/COLOR]; [COLOR=#00ff00]Fifth Star Vagabonds[/COLOR][COLOR=#faebd7] (Riddermark)[/COLOR]