When the most convenient, efficient way to get battle points is to NOT win, that's a problem.
You can attack Landing Zone sectors all day long, for5*5=25 total goods, win 79/80 battles, and then delete your siege army. You'll be challenging a +50 defensive bonus, but if you're farming battle points that's probably not an issue.
If somebody drops a siege on some other landing zone, you can go kill that siege instead, and you'll only be challenging a +0 siege army that's usually a mixed bag unless somebody is trying to set up a farming sector.
Removing all of the hostile NPC isn't going to change anything fundamental, you'll just have access to a few more bars when you're farming landing zones.
There are several bad ideas floating around, suggesting various ways to "fix" GvG, but they all have some serious flaws. Here are some suggestions that seem like they would help, even though they also have some :blink:minor flaws.
Allow sectors to be subverted, similar to what we see on the continent map, and thereby transfer goods between the two guild treasuries. Four times the amount of the Grant Freedom goods is probably in the right ballpark.
The costs of a "new" siege should be flat rate, regardless of how many sectors a guild owns. 100*5=500 goods per siege is probably in the right ballpark. "New" means that your guild has not had an active siege, anywhere on the map, during the past 5 minutes. (The current pricing structure just forces folks to use ghost guilds.)
Add a 30 second time delay when a siege is deleted or broken, so that a single alert defender will have an opportunity to replace their damaged garrison armies, or add additional garrison armies.
If a guild places another siege anywhere on the map, after the 30 second delay but before the 5 minute timer expires, rather than Goods the siege should require ACTUAL troops that would have used until they'd won at least one battle.
Get rid of the dynamic landing zones, and don't allow a single guild to lock out 20% of the map.
We have helicopters, for goodness sakes. All NPC owned sectors should be landing zone sectors, as well as all sectors at the edges of the map even if they are Guild Owned.