I write only in DADGAD. Feels like it’s been a very long wait with no news in sight now.
I can’t speak to the likelihood or timetable of any potential changes to the main guitar tracker, but for what it’s worth, my own main tuning (Guitar Craft standard, CGDAEG) also pitches below the guitar tracker’s low E2, and if that’s what you’re wondering about, I can speak to my own experience thus far with the MG3 Beta.
For me, when I truly need both six-note polyphony and the full range of my tuning (and more on that below), I use two instances of MG3, one using the guitar tracker and one using the (duophonic) bass tracker. I’ll use a Pitch Filter module in each instance to avoid potential collisions–for example I’ll filter the guitar tracker to respond from G2 on up to the range of my guitar, and I’ll filter the bass tracker to respond from C2 up to F#2. I’ll then feed both of these instances of MG3 to whatever instrument I’m targeting, and it’s pretty seamless. (And, it turns out, you can exploit two instances in a number of other ways that didn’t occur to me until I started setting it up. 
)
What has surprised me though, is that in practice, I don’t seem to need to reach for the multiple instances thing nearly as often as I’d thought I would. At first, I reflexively wanted to map everything to the full range of my tuning, and currently that requires the two-instance approach. My own reasoning is that I improvise a lot, and I don’t want to “run out of range” simply by reaching for a physical note, in the heat of the moment, that isn’t available to the guitar tracker.
I still think that reasoning is valid insofar as it goes, but the more I play “soft” instruments like the (gobsmackingly amazing) SWAM woodwinds and strings, the more I realize that my internal thinking is changing–honestly, learning to truly treat each instrument for what it is, and learning to treat the guitar as a controller. If the instrument I’m playing is, say, a piano, then it makes sense to use the two MG instances, even if I’m also going to use Transposers to go up and down the piano beyond the range of my controller. I can range all over the neck, and this makes logical sense to me.
But if I switch over to the SWAM English Horn, for example, that instrument’s range is much more limited; if I try and map it to the lowest octave on my tuning, I’ll “run out of range” for the horn before I run out of range on the guitar–so I’m already playing the game of it being a subset of my fingerboard.
And the more I play these things (they’re addicting) the better I seem to get at “playing the controller” to the instrument at hand–I can see that it’s actually becoming more natural for me to switch between a “full range” instrument like harp or piano, to a limited-range instrument like a woodwind or even the duophonic SWAM solo strings.
So, for me at least, as a fellow not-in-standard-tuning traveler, I find there is absolutely a place for the two-instance solution to cover my full range, but I actually don’t need to lean on it that much.
Hopefully this is useful to you. 
1 Like
I play in predominantly DADGAD these days too (Both electric and, of course, acoustic).
I use MIDI Guitar 3 HEX almost exclusively, all my guitars have a (roland) Hex pickup.
MG3 Hex allows for DADGAD and other tunings and works great – I mainly drive Ample Guitar plugins and some Kontakt guitar libraries with this.
Best
David
Sorry for delays. I planned the drop tunings for the update after the upcoming update (ie. 3.0.65).
2 Likes
Have you tried using the bass tracker?