Can you do it? Yes. Would I do it differently? Yes.

I would not bother with keeping 10.10. I would install 11.10 and keep it
simple. If you do not like Unity then you can add just about any DE to the
Oneiric base including Cinnamon from Mint.

But each person is different with varying needs, so what I would do is
unimportant. What is most important in answering this is what is your
purpose in wanting both Maverick and Oneiric?