Embodiments of thermally and chemically strengthened glass-based articles are disclosed. In one or more embodiments, the glass-based articles may include a first surface and a second surface opposing the first surface defining a thickness (t), a first CS region comprising a concentration of a metal oxide that is both non-zero and varies along a portion of the thickness, and a second CS region being substantially free of the metal oxide of the first CS region, the second CS region extending from the first surface to a depth of compression of about 0.17·t or greater. In one or more embodiments, the first surface is flat to 100 μm total indicator run-out (TIR) along any 50 mm or less profile of the first surface. Methods of strengthening glass sheets are also disclosed, along with consumer electronic products, laminates and vehicles including the same are also disclosed.