Answers to this question are opinions. Assuming that the stackexchange police permit that, here is my opinion.
The real objective is lowering cost through reusability. In my opinion, the VentureStar approach made the unnecessary and suicidal leap that reusability required single-stage-to-orbit. It does not. It was single-stage-to-orbit that killed VentureStar, because of how thin the margins on everything had to be. The SSTO assumption, and the use of chemical propellants, leads inevitably to a very fragile architecture where any noticeable mass growth will push you off the cliff. It is simply an accident of nature that the size and mass of the Earth and the energy of chemical reactions conspire to make single-stage-to-orbit tantalizingly close to, but not quite practical.
If you want low cost and reliable, you want robust engineering solutions with lots of margin. The way to do that is with staging. If you can recover one stage, then there's no reason you can't recover two. A single or a second stage has the more difficult environment to deal with, which is entry from orbit. The first stage will have an easier time surviving to be recovered, coming in at lower speeds from lower altitudes. SpaceX is now developing the capability to recover their first stages.
If you went nuclear thermal, that's a different story. Then you could do SSTO, if they let you. But I don't think nuclear anything would be low cost, even if reusable. If you can do reusable chemical, that will be cheaper.