My object here is not to introduce any new or original ideas but to suggest some changes simple enough that it can be done quickly and without too much effort by HTC. If you want to introduce new ideas please start another post so this one doesn't get too far off topic.
My suggestion is that we simply rearrange the field/city setup slightly. If I remember correctly the ack guns start firing at about a 3k range. I suggest we move the town to just inside that range so that the ack from the field can just barely cover the town and vice-versa. This would make it so that all ack from field and city would have to be taken down. The city would still be far enough away so that fighters and bombers would still not be close enough to take off at the last minute and strafe troops if you had the field capped.
Secondly, place the VH directly in between the field and city so that GVs can get to either one quickly.
I believe that these changes would bring back the importance of buffing to the level it was before and increase the toughness of capturing a field over what it is presently. I am suggesting these changes because they would seem to be very easy to implement, would be effective and would keep all of the cool strat ideas that HTC has come up with.