a few more things i want to add.
with the walls the defenders had for the first time in perpetuum a advatage. before that the attacker was always at the advatage. the attackers got the surprise. if even one gate scout was afk it was all for nothing at the gankers had a few easy kills.
with the walls the owner of the island could use the island for their own benefit. they could wall off entire regions if they wanted to, and as it seams it had in most cases the effect that was planed. no wall can keep anybody out of there. but it buys time. time to respond and time to get you miners or pve bots back and bring the pvp bots out. i think the alsbale natives have shown that often enough that they can pvp and do pvp. but not pvp like the persons that complain like. pvp for them is just to rush in and kill everything at is an easy target.
the walls changed that. they got no or very few easy kills. the walls kept them out for long enough. not stop them. but it gave you time to react. and if a overwelming force shows up then im realy sory that you did not get your 2 miners killed that were the only ppl online atm on that iland. but if you have the choice to fight a certain death with 3 ppl against a attack force of 10 or more. i think then it is acceptable to say that then we dont fight at all.
we like to fight and we do fight. and we have shown that often enough. what we dont like is to get ganked. and for that the walls were pretty usefull.
but back to walls:
the walls were used to create a realtivly save zone around the outpost with enough room and locations to do anything in it without beeing shot on a 30 minute basis. for that you need some decent mining or npc spots within that area. with the new patch (3000m) this will make the walls more then useless. the wall are not there to protect the outpost. that one dont needs a defense. the walls were there to protect the spots of intrest around the outpost. and there are nearly no spots of intrest in a 3km radius. with this the walls became useless, and there is no need for a medival fortress, because there is no gain in it.
if you would say 4000-5000m then i would say it still would have been of use. but with 3000 there is no gain. with this the walls will be broken to a way were there is nothing that it is worth to build and maintain them.