I don't get what idea you're communicating here. You seem to be saying that the best option for rockets is to accelerate upwards, out of the atmosphere, gradually transitioning to accelerating horizontally (if this is what you mean by baseline-3). Well okay, that's what we do, when using rockets.
Doing that with a track would be expensive because the track would have to be built hundreds of miles high over all of its length. It would be cheaper to build most of it lower, and maybe accept that we'll have to handle the air resistance somehow. If we build a track that doesn't go out of the atmosphere, we could still use it to build up a lot of speed and then turn the rocket upwards before the thing is self-powered. If we do build a track that goes out of the atmosphere, we'd still want to get as much ground-level acceleration as we can.
Maybe it's more practical to build the track on the Moon, where there's no atmosphere.
Doing that with a track would be expensive because the track would have to be built hundreds of miles high over all of its length. It would be cheaper to build most of it lower, and maybe accept that we'll have to handle the air resistance somehow. If we build a track that doesn't go out of the atmosphere, we could still use it to build up a lot of speed and then turn the rocket upwards before the thing is self-powered. If we do build a track that goes out of the atmosphere, we'd still want to get as much ground-level acceleration as we can.
Maybe it's more practical to build the track on the Moon, where there's no atmosphere.