You make me doubt, maybe your orbs disappear when you die (if someone can confirm) but it would have to be a complete wipe to be sure that there is no orb left (extremely unlikely, my team would be 4 titans, 2 hunters, come at me bro). If only one or two dies, they can come back and take all the orbs of the 4 others left. Because of radar it would be extremely hard for a striker to come in without being shot in mid air, you see enemy coming in. Bubble contains the FoH so you can just jump out when he comes in and back in. Two warlocks would not get through 4 bubbles, neither two hunters (if they aim to shoot at bubble, hunters can just run out and shoot them then back in)