I don't see cost/scarcity to fill X Plots for resources as an issue but a welcomed design. I would argue one person/ average player shouldn't be able to do what you are attempting. Managing/ resourcing 400 plots should be too time consuming and costly for most individuals to accomplish. Similar as to attaining and/or developing 400 plots of land in brick and mortar world would be too much for most individuals. Most who have as much got in early. Such is the benefit of getting in early.
Large plot owners might welcome cheaper workers. However Cheaper workers devalue the workers already available. Cheaper workers devalue the mined contents. We want scarcity. We want too many plots and not enough workers. Supply and demand then increases values of the workers (card packs) which then increases the value of the mined contents which in turn increases the value of land. I welcome land owners fighting over workers. Less is more has been a proven model in SPL.
The game starts with the cards. Card inflation/ devaluation isn't enticing anyone to invest in and hold sets. This trickles to card packs as well. Not that SPL can completely control such as funds are needed to run the business side and markets will market. Of course an influx of players will remedy all of this. I figured this a good as a spot as any to type this out on since you are a land baron and given the context of the post. All the best with your assets.
Why is land 32% full after years of launching?
How can we change that?
There could be multiple reasons that come to mind when pondering such a question but the reasons are only that, just a thought. One thought being: we are seeing the result of how many players we had when land was being designed and expected to have in the future (which is now) vs. how many we actually have today. I don't view it as a big issue though. With the assumption we gain more players comes more prospectors.
I'll take a crack at answering.
() More players joining the SPL universe that want to participate in land.
() Green Candles, people seem to participate more when things are green.