Advanced intermetallic β-solidifying γ-TiAl based alloys, e.g. TNM alloys with a nominal composition of Ti-43.5Al-4Nb-1Mo-0.1B (in at.%), are predestined for high-temperature (HT) application as turbine blades and turbocharger wheels in modern high-performance combustion engines due to their low density, high strength and creep resistance as well as their excellent oxidation behavior when compared to concurrent Ni-base superalloys. To improve their HT-potential, state-of-the-art methods based on high-energy monochromatic synchrotron radiation were applied in combination with an adapted quenching and deformation dilatometer on refined alloy compositions with a cumulative addition of 0–1 at.% C, Si and rare earth elements such as Gd and Y in order to study equilibrium and non-equilibrium solid state phase transformations, hot-deformation behavior, texture evolution as well as carbide precipitation kinetics. Complementary real-space imaging by means of scanning and transmission electron microscopy as well as lab-scale X-ray diffraction and hardness measurements on heat-treated specimens were performed for verification. Furthermore, the most promising alloy variants from the pre-study were characterized by means of creep and tensile tests and evaluated on hot-workability by uniaxial compressive deformation testing conducted with a Gleeble 3500 simulator. The adaptation of alloy chemistry and hot-processing allows defining a TNM-based alloy for an economical use until temperatures above 800 °C.