Looking for some advice for my Cavalier & Squire

[Javaed]

I'm working on an Order of the Cockatrice Cavalier who will be taking the Squire feat at level 3 and I was hoping for some advice as to tactics.

Background Info and House Rules:

I'm loosely basing the personality of this character off of Zapp Brannigan from Futurama and am bringing in a Squire so that I'll have a Kif Kroaker to play off of. To be clear, these aren't going to be the exact characters from the show, but I'm taking elements of their personalities as well those from similar duo's (The Lone Ranger & Tonto as well as Don Quixote & Sancho Panza). The squire may even be the DMPC for RP purposes, as he loves the idea of these characters.

My Cavalier is going to be Order of the Cockatrice and is using a house archetype that gives up Heavy Armor and my mount for EWP in a Blade, the ability to pick Fighter specific feats that select a specified weapon type and bonus combat feats every 3 levels instead of every 6. Additionally, for my Squire I can select from additional classes, but he still needs to be a somewhat martial character. He's going to be a custom race with a -2 to Str and a +2 to Dex and Chr.

So, the idea I'm toying with is a Cavalier who focuses on Feint & Intimidate tactics and a Ninja Squire (allowed by a house rule) picks up Butterfly Sting. The idea would be for my Cavalier to Feint the target, causing it to lose its Dex to AC, setting it up for Sneak Attack damage. When my Squire crits, he uses Butterfly sting to pass the crit on to the Cavalier, who will get an immediate AoO starting at level 8 (thanks to Steal Glory).

Some questions:
1) Does Greater Feint result in the target losing his Dex bonus to AC against all attackers, or just the against all attacks made by the person who Feints?

2) Can I combine Power Attack & Vital Strike?

3) Would it be worth going down the 2-Weapon Fighting route for my squire, keeping in mind that it will be 2-3 levels behind the rest of the party?

4) My Cavalier doesn't have to use an Exotic Weapon, just a sword of some kind. Since the plan is for him to be Vital Striking fairly often, would it be best to just stick with a Great Sword? Or should I maybe go with a Dex build, maybe with an Aldori Dueling sword.