1. Suffering's End, Unstable Gash, Ranger's Resurgence, Flickering Blades, Ringing the Bell, Reproving Strikes, Bloodlust Strike, Attacks on the Run, Hawk's Talon, Wounded Beast, Disruptive Strike, Hunt's End, Hunting Partner Strike, Marauder's Rush and all Beast Powers (But I'm not using a Beastmaster anymore, but just saying) all do not require you to have two melee weapons equipped. Ranger's actually have a surprising amount of powers that do not require a weapon in each hand, and powers like Ranger's Resurgence and Disruptive Strike are actually quite good Ranger Powers as well. Even the powers from Giantslayer don't require two weapons.
2. One Shield Proficiency Feat. I even had enough room for Shield Mastery and Specialization.