Represent the landowner in negotiating a 99-year ground lease for a prime downtown parcel intended for a 40-story tower. Draft the key economic terms regarding the initial base rent, rent resets (market value adjustments vs. fixed increases), and percentage rent clauses. Specifically, address the 'cure period' for tenant defaults and the reversion rights of the landowner if the developer abandons the project, ensuring the landowner retains the improvements made.