The applied magnetic field and its inclination angle play important roles in flow stabilization and energy distribution in the flow domain. In this article, the linear stability characteristics and energy distribution due to the combined influence of thermal, magnetic, and gravitational forces in a vertical layer of ferrofluid enclosed by two differentially heated walls are investigated. The objective of this article is to investigate the combined effects of thermogravitational buoyancy and magnetic forces and provide parametric guidance for mixed magnetogravitational thermal experiments. The numerical results are obtained by the pseudo-spectral Chebyshev expansion method. It is found that the qualitative change in the shape of the instability boundaries and the area of flow stability expands significantly when the field inclination angle increases. The destabilizing magnetic field variation effect is most pronounced in the near-wall regions, especially near the cold wall. However, the viscous dissipation near the cold wall is also stronger than that close to the hot wall. Consequently, the overall instability pattern shifts toward the hot wall. The thermomagnetic perturbations arising in the layer of ferrofluid tend to make the magnetic and magnetization fields more uniform near the walls. The instability is mostly driven by gravitational buoyancy due to thermal effects compared to magnetic effects. The perturbed kinetic energy is lost due to viscous dissipation and modification of the applied magnetic field in the flow domain. Ferrofluids under the effects of thermal, magnetic, and gravitational forces have potential applications in cancer detection, MRI scanning, oil separation from water, tunable optical filters, digital data storage, vibration dampening, energy conversion devices, etc., and many other engineering branches.