Yes I do think it has merit. How it would play out I am not sure, because there are so many terms.
For instance, when I talk about man's will being free, I mean that in time man is making decisions and is held accountable for them and is learning through them. I see this as "allowed by God with exceptions where He intervenes for our good", and all within His purpose who has predestined all things to work according to the counsel of His will(Eph1).
However, some people, when they hear the term "free will" believe the person speaking it means that everyone in the universe is cast adrift upon a random sea of events initiated my man and to which God is trying to react( Adam and Eve sinned so God sent His son, etc. laughable I know but believed my multitudes), that our salvation is purely a matter of our choice, etcetera.
In the reverse, some people, when they spake of God as sovereign ,mean that to the extreme that God initiates every thought and action that takes place in every being He ever created, and there is no accountability, reward or penalty because God is the source of good and evil- or that God has ordained some to be evil and pay the penalty and some to be good and reap the reward because He can do whatever He wants and doesnt care if we understand it or seek justice and equity from our Creator(Laughable also, but many believe it).
As you said, individuals from all over the spectrum of hybrid positions and hybrids of hybrids have a difficult time understanding one another. I believe this is a built in "Babel effect" from God. He has confused our language so we cannot get very far into the truth without the Holy Spirit. The Spirit always magnifies the cross(I am determined to know nothing among you but Christ and Him crucified). Babes stay in the "knowledge" of the word while maturing saints move on into the "wisdom" of the word. By "knowledge" of the word I mean terminology and systematic theology- the surface of the word.
By "wisdom of the word" I mean the underlying nature of God, the principles of the "whys" of God and the "ways" of God and walking in them.
Yet we do speak wisdom among those who are mature; a wisdom, however, not of this age nor of the rulers of this age, who are passing away; but we speak God's wisdom in a mystery, the hidden wisdom which God predestined before the ages to our glory; the wisdom which none of the rulers of this age has understood; for if they had understood it they would not have crucified the Lord of glory; but just as it is written, "THINGS WHICH EYE HAS NOT SEEN AND EAR HAS NOT HEARD, AND which HAVE NOT ENTERED THE HEART OF MAN, ALL THAT GOD HAS PREPARED FOR THOSE WHO LOVE HIM." For to us God revealed them through the Spirit; for the Spirit searches all things, even the depths of God. ...........
Now we have received, not the spirit of the world, but the Spirit who is from God, so that we may know the things freely given to us by God, which things we also speak, not in words taught by human wisdom, but in those taught by the Spirit, combining spiritual thoughts with spiritual words. But a natural man does not accept the things of the Spirit of God, for they are foolishness to him; and he cannot understand them, because they are spiritually appraised.
(1Co 2:6-14)
This is why, altho I would be glad to participate in an effert such as the one you have presented, I think it would probably turn into more "strivings about words to no profit in the hearers", because.........
No Matter how many times I define my position, the nuances of it, my understanding of certain words and what I mean by them, PEOPLE KEEP RESPONDING TO ME ACCORDING TO WHAT THEIR DOCTRINE HAS TOLD THEM MY WORDS MEAN :o). I don't think it is that people don't want to communicate as much as I think it that they can't communicate because they cling to their ideas so desperately as if the thought of letting go enough to examine an alternate possibility is tantamount to the fabric of the universe coming apart :o)
I guess tho, you could have each participant post a brief "position paper" about what they believe when they use a certain word- if we could find an appropriate filing system for it- it could lead to some mutual understanding, at least, among those who were really interested in understanding someone else, rather than just expounding their own particular views.