ZombieRoboNinja said:1. It makes sense that archers would prefer Defensive Mobility to Toughness, and probably wouldn't be sinking enough feats into two-weapon fighting to make it worthwhile (they'd be better off with a longsword wielded two-handed for the +1 damage), so I wouldn't say this is a huge problem. If I was making an archer ranger, I'd go for Defensive Mobility. (Plus, both archery paragon paths require the Archer style.)
My wife choose an Archer Ranger and took the TWF Toughness path so that she would not need to avoid OAs via shifting, instead she could just switch over to TWF when foes got past the front rank. Indoors, this works fairly well. Outdoors, she tends to go with TWF right off the bat. She also took Weapon Prof. Bastard Sword, just in order to do more damage over a Longsword.
Even shifting around, it's just too easy for opponents to continue to attack her, even though that they do not get OAs. So, her strategy is to mostly stay put and protect the party Wizard.
Course, she did not know about the Paragon Path requirement, so I'm not sure what she will do then.