And if you don't want to use the Kstep?

Only if you want to do something non-standard.
Like Homing?

I'll agree that the KFlop can be complex, as ultimately it is a pretty high end controller with lots of capability that lots of users will never use, but it's only as complex as you want to make it.
And my perception is that to do the same things that I can do in Mach3 and UCCNC, that the KFlop is much more complex.

Dynomotion needs to change that perception to get more people to use it.

I've had this discussion with my friend with the 2 KFlops. We both feel that it would be much more popular if it were easier to use.
It's not unlike Mach4. Mach4 is incredibly powerful, and at some point may well be the best software control available. But it's incredibly complex, if you want to do anything "non-standard".

My take is that all of the available software controls are designed for a wide range of application.
For serious users, they all require a fair amount of customization for specific applications. This is where the complexity comes in.