The map doesn't work for GVs at all, there's just relentless hording that is no fun to participate in or be on the receiving end of. It definitely does not work out of hours, which is when I'm able to log in, location and all. My opinion is based on a different experience to yours Chilli, which doesn't invalidate either position, however to get a fight or have a fun time in a GV I'd have to take time off work during the week or tell my kids to bog off in the weekend.
Until we have 600+ players logged in the big maps are just annoying.
I have yet gone to the central high altitude base in a GV and not had some fun experience. I do play at very low population times.
Next time the map is up, try this: If you don't own A21, take a M3 or M4 with HE and rockets if equipped attack the town. If you own 21, it is much easier to provoke a GV fight as there are no nearby airfields to stop your attack on the other fields. True you cannot capture any of them but you can still disable their troops radar and even their bases if you desire. Most likely someone will notice and come and try and see what is flashing their field and want to reserve their ability to launch an attack on A21 at some time.
^^^^^^
All that is just in ONE area. There are a number of Vbases in the middle of the contested furball areas also. If you want to go and sit at a spawn camp, then I guess this map won't do much for you when numbers are low. You have to think outside of the box. I realize that this statement is a little harsh and condemning of spawn camping (which I too enjoy, very much), and of course, as you have stated, your experience could just be differing from mine (could be country related even - some don't defend, some don't grab turf, etc.)