In this paper, we propose a universal power control (PC) algorithm that can provide QoS support in minimum signal-to-interference-plus-noise ratios (SINRs) for all users while exploiting differentiated channel conditions to enhance the network throughput. In particular, we design the PC algorithm by using non-cooperative game theory and establish sufficient conditions for its convergence. Then, we apply it to design a hybrid access scheme for two-tier macrocell-femtocell networks. Specifically, we devise a distributed load-award association algorithm for macro users, which enables flexible user association to BSs of either tier. In addition, we develop an efficient mechanism based on which users can steer the equilibrium in such a way that they achieve their desirable performance targets. Numerical results are then presented to validate the theoretical results and demonstrate the desirable performance of the proposed algorithms.