I agree that nerfing horde beacons would bring some benefit to the experience of most players in Unturned. Keeping your bases for a longer period of time is something that I think a lot of players would like. There are a few good ways that I think you could nerf horde beacons without outright disabling them. One of the main issues with a setting that disables horde beacons is that it conflicts with quests on Russia (and other maps?) that require you clear a horde beacon to progress through the quest. It’s not a huge issue, but it’s undesirable.
I think the biggest issue is the scalable loot. For the same cost of a horde beacon, a large group of players (who are already advantaged in combat and loot) will get significantly more loot per horde beacon compared to a small group or a solo player. This is unfair. Groups do have to slay more zombies, but the cost to make a horde beacon remains the same. Making the loot consistently the same for anyone doing a horde beacon is a good first step.
I would also like it if horde beacons were more risky. If an orange beacon of light were to appear in the sky right where the horde beacon is placed (similar to the white beacon at the end of the Mk II. quest), it would call attention to everyone on the server. Players completing horde beacons already had to consider players countering them, but now there would be a much greater risk of players attacking. I think this would cause groups to farm horde beacons less often, and make it more interesting with the real possibilty of counter-play from other players.
A final, smaller solution would be to change the crafting recipe. I would make it cost a portable generator, a spotlight (for the beacon effect), 2 raw explosives, 2 chemicals, a detonator, and a blow torch. This makes it a little more difficult to obtain and encourages more looting of construction zones.
Any one of these changes alone would be helpful in nerfing the horde beacons without killing their appeal. For the players seeking faster raiding there are always the 10x loot servers and so forth. For everyone else, I hope that this would increase the lifespans of many bases, and make raiding more rewarding by requiring more preparation to execute.