Quote by D H
You are ignoring the rocket equation.

Not sure height buys you very much.
Some velocity helps but the fraction of fuel you need is still proportional to e
^{dV}
if you need dV of 10km/s for Leo then adding 0.25km/s for an airliner isn't going to do much,
the optimum first stage drop velocity is something like 1/3 of the final velocity.