They sacrifice is their graphics and world clutter. AA's system could not be put in like so in WoW's engine - but the closest we have, is the Garrison system where you will see your plot in the phased selected area, or friends will see it if invited. AA's system is great but for massive servers, it is a suffering, especially with farming/sellers, and raiders taking the better spots (Your farm benefitted from being in certain zones). AA servers, as well, had less overall players than WoW servers.
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The best housing would be something where we are not able to offer all tools for the Garrison/Housing, but a minimal choice. (Do you want a Cooking station, and a workshop, or tanning rack and sewing room?), Garrison gave too much, and got worse with permitting the auction as well.