Future of Manned Space Exploration (Was the "NEXT" Moon shot...)

instead of another shuttle goes to the moon thread, some questions on
that vision thing

1. build a reuseable crv that can reenter from a moon or mars trip
trajectory.
2. build a heavy lift vehicle, capable of putting a bases on the moon
and mars.

is it a realistic budget, the reallotment of 10 billion a year
from other projects to complete a crv capable of multiple atmospheric
reentries, without the high maintenance of the current shuttle system
?
given that the crv would have more tasks, could it be refueled in
orbit ? like the proposed fuel pallet for the shuttle, an idea from
the early moon program -- launching the craft and fuel separately.

would it be much less expensive to improve the lift capability of a
shuttle c ? Using the OMS engines for more thrust. by adding larger
fuel cells as opposed to designing from scratch a new booster ? if you
did build a new booster, would it have much more lifting power, than
the current 100 tons ??