Mounted full attack vs Charging lance damage
The Roughrider is an interesting archetype. In some ways it seems to mandate multiclassing. (How else to get heavy armor prof for your mount? I suppose it doesn't really need proficiency if you aren't attacking with its natural attacks, but even so.) It gives a lot of mount protection and uses the mount as a vehicle to get you to the full attack, and eventually full attack spread out. Looks like it might be neat for a TWF build.
The Dragoon on the other hand pays hardly any heed at all to the mount, but certainly makes the lance your weapon of choice what with +2 damage instead of +1 for weapon training.
Either way I'll take at least 4 levels of Cavalier and the Horse Master feat for a full mount. Dragoon probably would take fewer levels of Fighter as the higher abilities aren't that interesting. The 15th level ability(ies) for the roughrider make for quite the 20th level capstone.
Roughrider version:
Gnome/Halfling Cav 4 (Emissary, Order of the Cockatrice), Fighter 16 (Roughrider)
1 Mounted Combat, Ride By Attack (Cav 1)
2 Spirited Charge (Ftr 1)
3 Taunt, Dazzling Display (Cav 2)
4 -- (Cav 3)
5 Power Attack (Cav 4)
6 TWF (Ftr 2)
7 Horse Master (Ftr 3)
8 ITWF (Ftr 4)
9 Trample (Ftr 5) (Etc...)
Dragoon version:
Gnome/Halfling Cav 11 (Gendarme, Order of the Cockatrice), Fighter 9 (Dragoon)
1 Mounted Combat, Skill Focus (Ride), Ride By Attack (Ftr 1 )
2 Spirited Charge (Cav 1)
3 Taunt, Dazzling Display (Cav 2)
4 -- (Cav 3)
5 Weapon Focus (Lance) (Cav 4)
6 Power Attack (Cav 5)
7 Horse Master, Dodge (Ftr 2 )
8 -- (Ftr 3)
9 Weapon Spec (Lance), Retrain Dodge: Shatter Defenses, Trick Riding (Ftr 4)
10 -- (Ftr 5)
I think I prefer the Roughrider version overall. Much more flexibility if you can't charge, although many class features die without the mount.
Order of the Cockatrice because it's got fun roleplay flavor. I also like Order of the Shield, but the edicts aren't as nifty.
Any suggestions, comments, or other?