  Entangled photon pair sources based on bulk optics are approaching optimal
design and implementation, with high state fidelities, spectral purities and
heralding efficiencies, but generally low brightness. Integrated entanglement
sources, while providing higher brightness and low-power operation, often
sacrifice performance in output state quality and coupling efficiency. Here we
present a polarization-entangled pair source based on a hybrid approach of
waveguiding and bulk optics, addressing every metric simultaneously. We show
96% fidelity to the singlet state, 82% Hong-Ou-Mandel interference visibility,
43% average Klyshko efficiency, and a high brightness of $2.9\times10^6$
pairs/(mode$\cdot$s$\cdot$mW), while requiring only microwatts of pump power.
