Fender colors. DO IT IBANEZ! On RG's too!
Solid colors in general would be cool. I love my TSG and the Espresso Burst is quite nice too.
I wonder if they'll make a pickguard version like the 224/2204 with 24 frets OR an HSS version of the 242/2402 like the Tom Quayle with 24 frets.
There were a few quilts on the prototypes we saw like the green one Lee Wrathe has.
Or how about this red one below?
Or they can go totally bonkers and do one in Desert Yellow.

Not to sound snobbish but one thing that should NOT happen is a standard Indo version. The Premium IMO is a good entry level to this instrument and anything else will probably cheapen it - kind of like how the RGA and RGD line were kind of derailed.
The Red one is Scott's Ibanez AZ from Polyphia - they were part of the "Test Group" that MArtin MIller and Lee was also a part of, basically all the people in the test group got custom Ibanez AZ's.
All of these Ibanez's I'll link below are based off the AZ. Some are very different, but they all have roasted maple necks, SS Frets, and the AZ body style. Plus like I said, all of these guys were part of creating the AZ style of guitar. In fact if you haven't heard POlyphia's new album yet, that entire album was done with AZ's - For their sound they used AxeFX and for the AxeFX patch they actually use a stock patch = "Boutique 1" Which I believe is modeled around a Matchless Chieftan amp.
Here are some other cool custom AZ guitars from the musicians a part of that test group that help create the awesome AZ series:
Mario's pink AZ from the group CHON
Tim from Polyphia's new custom Black&Gold AZ-Style guitar
- This doesn't have the alter switch, it has some nice lipstick style single coils - modeled around the HSS AZ.
Scott from Polyphia's new Tiger Burst w/pickguard AZ-Style guitar
- Again, same thing with Tim's above - clearly modeled around the AZ, roasted maple, looks like same neck, just no alter switch.
Erick from CHON's black AZ - this was actually one of the first AZ's they made - same as Martin Miller's and Lee's - note the white fret markers, like Lees.
Tim from Polyphia's Shell Pink AZ
Limited Japan Only Edition - Myrtle-wood Flame AZ
- This one isn't an artist AZ - but I think for all the AZ's available to us normal people, this one is probably my favorite. You can buy it on eBay direct from Japanese Guitar shops for like $4,000.00. Not worth it, but maybe to the avid AZ collector - this would be a great color for the standard color choices for 2019 Prestige I think - I know I'd buy it if it was just a normal Prestige price.
Then lastly my AZ! This is the first Indo-made Premium I've ever purchased. I have to say, it is amazing. Since the frets are stainless steel, that covers up for the questionable fretwork you can get out of Indo. I'll tell you what - Next to my American Professional 2018 Strat, I'll take my premium Bocote Espresso Burst any day. These frets are like butter. No wear, and butter smooth. Plus same pickups in the premiums as the prestiges, SD Hyperions. Lastly out of all the 2018 AZ colors - this one was my favorite.