Frankly, I don't trust the intelligence of people who don't have an internal monologue. If you don't think in words, you can't be thinking of anything very complicated
It's inherently progressive because it counteracts the inherently regressive distribution of property in a capitalist economy.
Taxes are not either flat or progressive. They are flat, proportional, or progressive. This is a proportional tax which targets unequal distribution to achieve progressive results.
If you mess with the rate, the system will be more easily exploited by the ultra-rich.
Not with a regular property/land tax. There's essentially no way to game that.
My point is that adding frills to a tax (like making it progressive) usually just enables the people with the means to do so to take advantage of provisions protecting the poor. A property tax is effective because it is inherently progressive and doesn't need to be tweaked much.
There'd likely be a lot of ways around it. Large plots would be broken up into smaller legal boundaries, parts would be owned by shell companies, parts would be loaned out and rented back at low rates, etc. etc. They'd find a way to take advantage of it to pay less than anyone else.
A straight-up land tax with no frills does the job. If it ain't broke, don't fix it.
Frankly, I don't trust the intelligence of people who don't have an internal monologue. If you don't think in words, you can't be thinking of anything very complicated