At least for launch, I doubt we'll improve those mass ratios for a long time to come - chemical rockets hit theoretical limits at exhaust velocities/specific i

At least for launch, I doubt we'll improve those mass ratios for a long time to come - chemical rockets hit theoretical limits at exhaust velocities/specific impulses of e.g. ~5.5km/s for hydrolox, and SSME already got within 10-20% of that theoretical maximum. All of the systems that can get better specific impulse, like thermal rockets or electric thrusters, have thrust:mass ratios waaaaay too low to get off of Earth on their own. (Possibly nuclear thermal rockets? But I don't think people will be overjoyed firing those off in an atmosphere.)