500 points is really rough, Especially for Blood angles.
The librarian is a sold choice for BA, but i would consider dropping might of heroes for blood lance, smite, or shield of sanguinius
I would consider either going jump jet or mech with your troops.
I have played both styles(jump angles and mech) i found that mech just survives a little better...but the jump jet versions when you field them look cooler in my opinion and are a bit more fun to play.
"When you get to heaven may the Devil be your judge.."