On Longbow I have found that controlling Bravo isnt always the best decision because its simple for the enemy team to control 2 wraiths and well guard A and C with said Wraiths. i have found that controlling A and C give the best option for map control. The way i have explained it to my friends i play with is this:
right off spawn have 2 people rush the closest base (either A or C) while the other 4 rush the opposite one(Ex. if 2 rush A then 4 go to C or Vice Versa) Once The first base(A) is secured have one of the two get in the wraith and either help secure the opposite base(C) or guard the current base(A). Once we have taken the second base(C) have one of the 4 return to the first base(A) to help defend it and another person take the 2nd wraith which guard the second base(C). So by the time this is done theres a wraith at A and C along with 2 people inside each guarding the base. While the enemy team has strictly B to use. A second option would be to have the 2 people in A and C go on the offensive and take B while leaving the wraiths to guard the bases.