IMHO, your best bet for IMAP mail on console are
Cone or
Mutt. I'm using Mutt.
While Cone does include some basic Usenet functionality, my favorite console mode NNTP client is
slrn.
If you don't like slrn, try out
trn or
tin. It looks like tin is still being maintained, while trn is not.
Before using any newsreader, make sure you check out the
GNKSA/2 evaluations of the product.