Just read the Air and Space article about capsules (Apollo type)!
A reunion of old experts like Myers, Cohen, John Young and Vance Brandt.
They had no notes and everything in their brain!
If they scaled up the Apollo capsule by only 8%, they could allow a crew of 6 or 7 while using the same kind of Launch Escape Tower and parachutes.
Everything inside will be changed except the hand controller. It will need to be able to land on Earth (rather than the sea) and its fuel will have to be able to still be working even after months if not years in space.
The heatshield will be better and even removable in such a way that the capsule could be re-usable.

Now, about the Moon flights (of the future).
If the idea is a rendez-vous between two separately launched vehicles (a Lunar Lander (LL) sent early and in Lunar Orbit plus a manned spaceship with the capsule) then the capsule will have to be launched within a very short launch window for a rendez-vous around the Moon. That rendez-vous might take several days even after Lunar Orbit Insertion, to catch the LL.

Could the LL be re-usable? Would that be wise? How is it going to be fueled ? With a cargo ship for Lunar orbit (sort of like a progress vehicle)? Maybe the LL shouldn't be reusable but built very lightweight and very simply (no pressurized hull for instance).

Maybe a new kind of rocket should be built (or an existing one adapted): one capable of either landing 10 tonnes on the Moon (but not taking off again) or one capable of orbiting 15 tonnes around the Moon.

I think I read somewhere that if one wanted to land 25 tonnes on the Moon surface, 50 tonnes of spacecraft and fuel would be needed at the moment of Trans-Lunar Insertion (leaving LEO). Is that too optimistic?

Raoul