Abstract: For years, the Laser Interferometer Space Antenna (LISA) was the "queen" of space-based gravitational-wave astronomy. LISA was designed to detect gravitational waves (GWs) from a wide variety of sources, including Galactic compact binaries, massive black hole binaries, and extreme mass ratio inspirals. Detailed scientific assessment led to robust predictions of its detection and parameter estimation capabilities. However, in 2011, budget realities ended the NASA-ESA LISA partnership, effectively killing the original concept. A host of potential "heirs to the throne" have since arisen, both in Europe and the United States. Each must be carefully evaluated in terms of cost, risk, and of course, science. I will describe these new detector concepts and compare their science performance with each other and with original LISA.