Drop the undo function - use step back / step forwards instead

I'm working in Photoshop, trying out stuff, as you do. Often that means backtracking if an idea didn't quite work, or if you made a mistake.

In Photoshop (today) hitting cmd+Z undoes one step - and redo does 1 step

In Photoshop (tomorrow) I would like to see cmd+Z stepping back through my history (and redo stepping forwards). Functionally, pragmatically there is only a benefit to doing this. 

So my idea is: throw the old undo function into the trash - totally wipe it. And have only step back/forwards through history. It would allow you to do the same as before - and more! (while simplifying the interface by getting rid of duplicate functionality)

thanks! =)