In the early 1960s, Rocketdyne considered a "pinwheel
rocket pump"--which sounds pretty close to what you are
suggesting. I always thought it was potentially a good
idea, but I don't think the Rocketdyne pinwheel got much
past the briefing chart (before viewgraphs) stage.

I agree with you that the greatest need for component
development for space transports is the rocket engine.
Rocket engines are basically simple and should go a
long time between overhauls, but don't. There are some
other things about rocket engines that come to mind when
integrated with the total vehicle--but that will have to wait
until I publish our newest concept that depends upon a
number of system "design tricks." A hint: these design
tricks enable a challenging, but, IMO, feasible, low empty
mass for a very large vehicle--a marriage of a number of
earlier design concepts. :)

Best regards,
Len
PanAero, Inc.
(change x to len)
http://www.tour2space.com