Abstract: Gate-defined quantum dots in Si/SiGe heterostructures are a promising platform for spin-based quantum computing because many device parameters can be tuned after fabrication. This tunability gives the platform its flexibility but also makes devices hard to operate reproducibly as they grow. This dissertation uses tunability deliberately in two ways. First, dynamically pulsing a single barrier gate resolves the conflicting tunnel rate requirements of latched readout, enabling single-shot readout of a quantum dot hybrid qubit with a signal-to-noise ratio of 10.2 and a factor of 15 faster reset. Second, gate-biased illumination reshapes the electrostatic environment, shifting a triple quantum dot into a low-voltage regime with a factor of three improvement in voltage uniformity and no measured increase in charge noise. Together these results show how the same gate control that complicates Si/SiGe quantum dots can be used to bring nonuniform devices into a range compatible with compact, scalable control electronics.