Coming late to the chat, but...
First, would you rather the focus be more on vehicles, more on drones, or evenly split?
At least 50/50, if not 40/60 in favor of drones.
Would you rather vehicles be more civillian style, security, or military? (For instance, 60 civillian/30 security/10 military, for percentages.)
Sounds about right for most runs. Hopefully civilian can also include some Municipal-types that would also share the roads and alleys, such as street sweepers, Garbage trucks, Fire Hook and Ladders, etc.
Would you rather the drones be more civillian style, security, or military?
Civilian probably should have the smallest off-the-shelf variety (because this is where Build-it-from-Scratch should be), then evenly split between security and Military.
Would you rather have fewer things with large write-ups and art (For example, Run and Gun style) or more things with smaller write-ups and little-to-no art (Similar to the SR5 core book)
Less write-ups I think and more stuff. Riggers are plenty imaginative: if you build it they will come (and take it. And play with it).
Similar to a bit above, how would you like to see a split between ground, air, water, or "other" transportation? (Shadowrun! In! SPaaaaaaaaaace!)
Personally, I'd say 30/30/30 and 10 for other.
Mods would seem a no-brainer, but would you like to see a "Build-it-from-scratch" system, or is that a waste of space since no one buys a Facility?
If you can build a Rigger Control Console from scratch--and you can-- why not the drones for it?
Should Autosoft and Pilot programming rules be found in the Rigger book or in the Matrix book?
The Rigger book. It's the first place most people will think to look.
What vehicles/drones that have been published in previous editions need to make a comeback? (Merucry Comet or DEATH!)
*Ahem* I brought a list...
The California Condor/ Spinrad 720: Hoverboard technology is just around the corner as it is...
Mitsuhama Nadeshiko Android Series: I'm serious here. Perfect for pixies (pixie-sized rigger tank, and you have an exosuit) and trolls working in repo. And anyone who needs a thousand faces.
Honda Viking: Big folk need a few more bones thrown their way than the arctypical Scorpion.