Kerbal Space Program is such an amazing game that secretly teaches you physics.

What about something like nuclear pulse propulsion, or some kind of massive spin launch?

With a denser atmosphere, wouldn't that mean that you could get more lift from a traditional aerofoil than on earth? And if so, wouldn't that technically make it easier to start from a high enough altitude that at least some of the gravity is mitigated?

Check out the “tyranny of the rocket equation”.

Or ask Randall Munroe How many model rocket engines would it take to launch a real rocket into space?

Build a large enough magnetic rail launcher and you could save shit tons of fuel. Get a ship doing 2000 mph before it leaves the ground and needs its rockets and you'll have a pretty good head start.

You don't have to launch from the ground, there are many things that can be done to allow them to reach orbit. It'll be an enormously bigger undertaking but the physics doesn't make it impossible. No reason to think of it in terms of our current situation either, and we are behind our current level of possibly when it comes to rocket science, due to * waves at everything else *

tidally locked

Wouldn't that be a non starter for life? One side would be perpetually baked and the other would be frozen.

you'll spend more time fighting gravity

Aw man. This is already a significant portion of my day.

I think Mars, assuming you terraform it, would be pretty close to that on both counts. Space planes might still be difficult, but the delta V is much lower and Olympus Mons would pretty much sit above the atmosphere.

Classic planes require an atmosphere to generate lift. There's an outer limit where that would be a viable mechanism, and on Earth it's still far below LEO. Still too deep in the gravity well for ion thrusters to be viable. It requires chemical rocket fuels to bridge that gap.

Maybe someday fusion propulsion will break that limitations, but for now the best you can do is reduce the amount of fuel needed by flying to the upper atmosphere and reaching hypersonic speeds before kicking into rocket fuel propulsion.

Then after orbital injection, switching to ion thrusters to move around, and solar sails for exiting orbit into interplanetary/lunar routes.

That's not how.......what???

F = G * (m1 * m2) / r^2

Note that radius is both squared and the dividing term. More distance = less gravity

That's, uh, not really how that works. A taller atmosphere would mean you have to go through more of it, but unless it's not a terrestrial then the atmosphere won't be that much taller.

If it is a non-terrestrial planet, it's unlikely anyone would be building rockets on there to begin with.

You're sort of right. The change in distance from the surface is insignificant, but a spacecraft orbiting a bigger planet has to travel further with each orbit so its speed must be faster to avoid falling out of orbit, even if the gravitational acceleration at its orbital height is the same.