As of June 2015, these re the key modules to have if you like to look deeper into how the words get their root meanings:
ABP+ (Apostolic Polyglot Bible) A wordy title but a great companion to KJV+ because the ABP Has the OT in Greek (LXX).
AMP (Amplified Bible - I always recommend the purchase of this module) - 100% of the time.
JMNT (Jonathan Mitchell New Testament) Better than the Amplified - fixes how the many of the verbs in English should be rendered in all the mainstream translations but are not. Example: JMNT often adds adverbs like "habitually, continually".
AS (Awful Scroll Bible) - love it for its concise descriptions and yet in an archaic way.
CLV (Concordant Literal Bible)
LITV (JP Greens Literal Version of the Bible)
On my wish list still...SAAS translation from the Orthodox Study Bible (LXX). That Bible is worth the $30 just for the notes in the Psalms!