Hm,
Nothing really stands out to me as causing massive lag, Nathi. At least not from that Screenshot.
But I see you have Vertex Groups, have you Parented the Vertex Groups to the Bones?
If there is no Deformation and the parts of the Bracket are separate Objects, you could Parent the Objects to the Bones. That way each Bone only has to move an Object, instead of a bunch of Vertices. I can imagine that would make a difference (especially if the Objects have many Verts).
