My printer's mainboard is a tired little 8-bit AVR, and it's always shown it. Push the speed and it stutters, because the poor thing can't compute the step timing fast enough and ends up starving the motors. I'd more or less accepted this as the cost of cheap hardware.
Then I flashed Klipper, which I'd seen mentioned in passing, and the printer started flying. The trick is almost rude in its simplicity: Klipper does the heavy kinematics and lookahead on a Raspberry Pi, then ships the AVR a precise schedule of step times to execute. The microcontroller stops trying to think and just does as it's told, exactly on the clock. All the real maths happens on a chip with actual headroom.
The result is the same printer, same motors, same belts, producing noticeably faster moves without the stuttering, and quieter corners because the lookahead is finally doing its job. I changed nothing mechanical. I just stopped asking an 8-bit chip to do arithmetic it was never going to manage in time.
Config is a single text file rather than a recompile per tweak, which is its own small joy. It took an evening and a bit of squinting at pin definitions. Worth every minute.