I would like to recommend my current favourite Greek Text which I have
been using to teach a Beginning to Intermediate class.  The first point
however is that this is strictly KOINE and then NT Greek.  It is not 
a classical text.  It is "Learn to Read New Testament Greek" by David 
A. Black.  I've used some other texts and this is by far the most user-
friendly text I've used.  It has some weaknesses, like all of them, but
they are far out-weighed by the advantages of the text.  However, I will
point out that since you have already studied Classical languages, then
this may be a tad too simple, with respect to what he thinks you don't
know.  But then, it is better to err on that side.  He is also sensitive
to the linguistic principles governing the language which are a big help
for people trying to understand it.  All my students enjoy the text.

James Smith