KiCad is still the preferred interface.

The original point stands. Ngspice shows its heritage from the days of Fortran far more than a modern code base would or should. It's sole great virtue (from my point of view) is that it integrates with KiCad and only falls over with no reason about 5% of the time.

I would suspect that some of the simulation systems coming out of the Julia community or Xyce would be a better base.