The one I daydream about most would be FAS pickups/electronics. Take the Fishman Fluence multiple pickup voicing thing to a whole new level...
I'll see your FAS pickups/electronics, and raise you an FAS "Virtual Whammy Bar" tremolo system....
My daydream is that the guitar is actually hardtail: When you move the whammy bar, you get no change in the tension on the strings. The whammy-bar is connected to real physical springs, but the bridge saddles aren't.
The whammy bar works in conjunction with the FAS stereo-output modeling pickups, applying a pitch-shift effect to each string individually, which tracks the position of the whammy bar.
I expect the system would be powered by a USB-rechargeable power pack, like the Fluence pickups you mentioned.
But it would also have a built-in Bluetooth transceiver which allowed it to "talk" with a stompbox-like base-station.
Using this base-station, you could:
- customize which pickup sound was modeled for each position of your 5-position switch;
- customize the pitch-shift range (upwards and downwards) for your whammy bar;
- automatically change pickup model in response to MIDI program change messages sent from your Axe FX III or MIDI footcontroller
- connect to a computer to download new pickup models and whammy settings from the large community
...and all without defacing the front of your guitar with a bewildering array of knobs and switches.
Still, all the actual modeling would be inside the guitar, not on the floor. The base-station only sends commands to the guitar via Bluetooth.
That way, if the base station breaks down, you can still switch sounds normally using a 5-position "soft" switch. (At least, until the battery pack runs out.)
All of this is way beyond what the VG-88 could do.
In particular, the pitch-shift ability for the "Virtual Whammy Bar" would need to be very fast-tracking and realistic to pass muster with most guitarists. Same with pickup models.
But, think of the advantages, compared against a normal magnetic pickup and Floyd Rose...
1. If you break a string, the guitar remains in tune;
2. The spring tension on the arm can be set however you like, allowing uptrem, yet double-bends still remain in tune;
3. All strings rise/fall in pitch while remaining in tune with one another, like a Steinberger Trans-Trem;
4. You can have virtual alternate tunings, just like a Variax;
5. Every pickup sound you want, every guitar sound you want;
6. Oh, don't forget: It's stereo output, so that you can have a layered piezo sound;
7. You could program certain sounds in your Axe III to use certain pickup sounds on the guitar, and let it do the switching for you;
8. It could also change the whammy bar sensitivity/range for different sounds/programs, or even disable it for an acoustic guitar sound.
That, I think, would be the ultimate combination, if the quality were up-to-snuff.