If you could solve one problem...

[sdr1]

The question is a bit too simple. Different 3D printing processes have different problems. Issues you might have with a resin printer (eg: messiness, adhesion difficulties, expensive feedstocks) don't necessarily apply to FFF printers, which have other problems (lack of soluble support material, clogging, dribbling) or powder-bed printers (abrasion, clumping, contamination). If you narrow your focus to a particular process - or even better, a particular machine - the answers you get will be more coherent.

Andrew Werby
www.computersculpture.com

I think you are right about the fact that narrowing the question could result in more specific answers. It was my intention, however to first look for more "global" issues, universal for all types of processes. Let's see how this approach takes us.
Thanks for your inptun nonetheless!

drive systems used in FDM
with proper feedback servo style control and bigger servos / steppers i can see print speed well over 1000mm/s within reach granted a extremely strong frame will be needed.
I'm prototyping a system now and i can safely print at 450mm/s with .05mm layers jerk settings over 100mm/s accel well over 10,000mm/s
i plan to make this into NEMA 23 and NEMA 34 Backpacks that just feed in data over I2C, SPI, Serial, or USB
stepper driver is built controller is 32bit based and well include a 600 count rotary encoder.
I'm also toying with Brushless motors.

I must admit, I don't feel my current technical understanding of 3d printing process allows me to fully grasp the issue here. I think I get it more or less though, and I hope the system you are working on will work as intended!