as a rule of thumb i always go for the vh first then field and town ack, second i try to rally other friendly's to help take the town down, this is not always the rule of course, because most people are more concerned with hovering over the runway waiting for someone to up.
take for instance yesturday at 21, morph you were there, during the first couple minuetes after reset.
i took the vh down then every one helped with the ack and then people started working on the town, but what we failed to do was take down the fighter hangers, and what happened next was too many enemies started too up, we just couldnt hold them back, and we failed to take the base.
so in the end id say that situation will determine what needs to be done. always take down the vh, and if a large number of fighters are upping then take down the fighter hangers as well.
if there are fighters getting up then you cant worrie about town because the goon will most of time, never make it.
you need and no **** cap before worrieing about the town