I think resident auctions would do so much...
1) It's faster to sell
If you can set a time limit on an auction, then you KNOW that the land will be sold by the end of that time period. And when each month's tier is based on the peak amount owned, the right timing can mean a lot. No more waiting and hoping.
2) It's easier to sell
You no longer need to know what your land is worth, and try to guestimate a fixed price you think someone will buy. Now the market would set the price. No more guessing.
3) Sellers have more exposure
As every auction nears its closing bell, it moves to the top of the list where it is highly visible. Every auction is guaranteed it's moment of top billing. No more obscurity.
4) A prettier world
No more floating, spinning, glowing, sparkling, animating, notecard-throwing, FOR SALE signs.
5) Open sales records
With every completed auction a matter of public record, no longer will the actions of a predatory few go unnoticed. But even more important, with open records, the true historical value of land can be known, resulting in fewer and lesser extremes in price fluctuations.
6) Fewer newbie "twitch" buyers
High priced land sales often go to the inexperienced buyers who haven't yet learned the relative value of things. When land purchasing is as simple and immediate as point and click, hasty mistakes are often made... And preyed upon.
With current transactions prominently displayed (#3), easy access to previous land sales (#5), and a N-day waiting period till the auction is over, new players have more time and information to make GOOD decisions.
7) Land flood tools
With more land being added at an ever increasing rate, AND all the land that exists (and that will exist) changing hands regularly, there is a vast number of land sales each week, and the number will only climb. A good auction tool will need to be able to filter and sort through all this information. "Show me all the land for sale in these sims." or "List all mature parcels between 512 and 1024 m2" or even "Email me if any land in Ahern comes up for auction"

Fair prices
The price will be set by the BUYERS and not by the sellers!
9) Fair prices
The price will be set by the BUYERS and not by the sellers!
10) Fair prices
The price will be set by the BUYERS and not by the sellers!