That is true, furthermore Overload has an usermade campaign called Overload: First Strike, which is a conversion and upgrade of the entire Descent 1 campaign to Overload. Additionally I recommend Desecrators, which is a Descent-like with procedurally generated maps. Think Sublevel Zero or Everspace, except good.
Now all that's missing is a spiritual successor to Terminal Velocity. Or at least I think so. There's like a 10% chance that game was one of those games that was seriously held up by how much its soundtrack slapped.