Logos 5: Is an upgrade worth it?

Technical, first-world problem alert: This post assumes familiarity with the major Bible software programs (Logos, Bibleworks and Accordance), and an interest in electronic resources for the study of Greek and Hebrew.

Despite the incessant advertising, I haven't been able to convince myself that shelling out 100's of $ for an upgrade from Logos 3 (Gold) to Logos 5 is worth it. Special upgrade prices expired last month, but I have an offer of academic pricing at 50% off until mid-May, so I can still think about it. What am I missing?

Let me explain my situation in a bit more detail, and then I'll look forward to suggestions:

• I use Bibleworks all the time. It is always open on my desktop. I consult it regularly in preparation for teaching, in general Bible reading, and in research. Bibleworks comes standard with morphologically tagged Greek texts of the New Testament, LXX, Apostolic Fathers, Philo and Josephus, as well as a morphologically tagged Hebrew Bible and morphologically tagged Aramaic Targumim. It also has more translations in more languages than you can shake a stick at. The best Greek and Hebrew dictionaries and Marty Abegg's tagged sectarian DSS (to name a few of interest to me), are available as add-on modules. I hesitate to pay good money to duplicate what I already have. 
• I do not require a library of commentaries or other resources on the whole Bible since I teach and research in a more limited area. When I start to teach a new biblical book, I will build up my library accordingly. No doubt a complete set of good commentaries would come in handy from time-to-time, but not often enough to justify paying for a set that will sit mostly unused on my virtual shelves.
• I am interested in more sophisticated ways to analyse and perform original-language grammatical searches on the Bible and related literature.

Questions about Logos 5:

• A minimal cross-grade would give me access to a few new Lexham tagged texts and reverse interlinears, some pictures, and a few new datasets that would allow me to search by phrases instead of words. I'm just not sure I would do this kind of search enough to make it worth $130. (The Logos sales rep I talked to actually said the cross-grade isn't worth it. What I should really do, he said, is shell out $1,000+ for one of the larger packages.)
• The Biblical Languages Upgrade looks more up my alley, except that I already have at least one morphologically-tagged database of everything in the package. What is the value of having multiple tagged texts of the same corpus? What is the benefit of reverse interlinears when any searches I do would be in the original language? I am open to being persuaded here. I'm just not seeing it. (If they threw in Moulton-Howard-Turner or the Lexham Discourse Greek New Testament Bundle as part of the package, it would suddenly look a lot more attractive.)
• Which of these modules is worth the asking price?

How about independent resources: The Göttingen Septuagint, for example, is very tempting, and--as far as I know--not available on any other platform. If you were to purchase specialized resources geared towards work in the original languages, what would you recommend?