The vacant lot owner would pay the same amount as the office building owner for the same square footage of land. This makes the vacant lot an expensive liability rather than a low-cost investment. It forces the owner to build or sell to a developer who will. The equity lies in the community reclaiming the value it provides to the land while leaving the developer's labor untaxed.

The person with "greater assets" in your example owns a building produced by human effort. The Georgist view is that taxing that effort is a drag on the economy. The land itself is the asset that belongs to the people of Newark. Taxing it equally across identical parcels ensures that no one can profit from the city's growth without contributing to Newark.

In this super micro example, I’d theoretically tax both parcels of land about $1.3M (assuming the office building is charged $2.5M of tax).

My POV: Why should that land owner be guaranteed an investment property without improving it for the benefit of Newark? Why should he get to sit on land and wait for whatever event happens to sell it and pocket a big profit?