Unless they think this out very well, it will be the end of small friendly guilds.
DAoC had to put in checks and balances such that if you owned a whole lot of keeps, the NPC defenses would get weaker and weaker making it easier to lose one.
A guild like Storm could have a dozen or more of these things making them even more attractive.
I've always hated the rat pack mentality of big guild gets all the loot so it attracts more people and gets bigger and is able to get more loot and more people join because now you 'have' to be part of uber guild to get the good loot so they are now bigger and can own several pieces of land and get guild bonuses so now you 'have' to join them to get the bonuses so they get bigger and are able to take over more land ....
The smaller the guild, the harder it should be to take away their property, the bigger the guild, the harder they should have to work to defend it. Otherwise, simply call this the Storm/Council bonus pack.
Why bother buying the Booster and your guild shelling out a 100 million credits if Storm or the Council is simply going to come over and 'own' you. I want to defend my land, but not against 300 other lvl200 players.
They will have to break this down into brackets somehow. Based on the number of people in you guild, you may or may not be able to attack a guild's compound. If my guild has 30 people in it, then I would expect our compound to be attackable by guilds with between 20 and 50 members.
If my guild's average level is 100, then I would the above restriction to apply and other guilds would have to have an average level of between 90 and 110 to attack our compound.
This way we set up equal forces on either side of the struggle for control of the compounds.