what if you really need money, and you sell your own land for next round auction, and start price is higher than everyone's money? then you won't be able to sell in the end even if you would be willing to price it lower.
percentage chance would be nice..right now it seems like its completely random whether plots will be up for sale, and adding a little element of certainty will encourage some planning - whether you want to keep saving assets for the same long term strategy or secure that land asap and dump to the market