Mass-wise, yes, but long term fuel storage and transfer in a vacuum is all completely theoretical at this point
I doubt it would be practical to pump fuel to another rocket. The obvious thing to do is store the fuel in orbit with its own rocket engine. Then you only have to dock with it and turn on the engine.
Solid-state boosters are potentially even better. No boil-off of fuel to worry about
Good idea! Although solid fuel rockets cannot be throttled or turned off.
You still have to land all the fuel to get the people off of Mars
Yes, but that's a lot less fuel than a return trip from Mars.