Most people running 2 hand use rally for the major brutality buff, but more importantly the heal it gives. If you run rally with bird of prey you will get 28% damage buff, a great heal, major expedition, and major endurance.
For pve you could get away without rally and use netch, but for pvp you really want that heal so I'd recommend rally and bop.
Bird of prey buffs proc sets, netch doesn't. With the right skill lineup and CP you can easily get a 17k selenes.
If you run rally with bird of prey you will get 28% damage buff, a great heal, major expedition, and major endurance.