A washing machine appliance, including one or more methods of operation, is provided herein. The washing machine appliance includes a wash basket rotatably mounted within a wash tub and being supported by a front bearing and a rear bearing. A method of operating the washing machine appliance includes rotating the wash basket within the wash tub at a basket speed and obtaining a front displacement amplitude, a rear displacement amplitude, and a wobble angle of the wash tub. Based at least in part on these measured values, front and rear bearing force amplitude thresholds and virtual bearing force values are calculated and compared. If the virtual bearing force value of either the front or rear bearing exceeds the respective bearing force amplitude threshold, an operating parameter of the washing machine appliance is adjusted to limit bearing forces resulting from out-of-balance loads.