How about adding "A concordance to the Greek Testament" by W.F. Moulton and A.S. Geden?
I'm curious what value you would find having this in Logos versus just using the Logos Morph search to search for a Greek lemma in whichever Greek text you prefer? The Logos searches are supposed to replace and be better than any concordance.
How about a comparison. Here's the entry for ἄβυσσος (abyss) in the Moulton/Geden:
and here the Logos search for the word:
Same list of verses, but the search results are better formatted and can be manipulated in a variety of ways that a static concordance cannot.
