I really love the KiCAD ngspice integration. It’s a door-opener for faster, more reliable designs. But it lags a little bit of comfort, as no generic ICs are available.
It would address so much more users, if generic Transistors, Opamps, Comparators, References, were available.
I suspect that the reason is (like with 3D models) that simulation models coming from vendors have some kind of licencing that clashes with the open distribution…
Model parameters are here: Spice models and model parameters for ngspice circuit simulator. And the basic model parameter set has some simple models of common devices.