New M2 inconsistiencies

Looking for a bit of assistance. I have my new M2 setup and ready to run. Calibration seemed to do well. The first square was tall and narrow, the second one was spot on at 12 inches. I was feeling spicy so i figured what the heck I’ll try cutting out a whole parametric chair on the first go… 4 hour project not so bad right?

Well… Things seemed to start out fine. I did a test on a single one of the cross pieces to confirm that the gap in the chair slats that grabs the material was indeed 3/4 inch wide. It was so I uploaded the whole chair and off to the races.

Straight cut bit
.2 cut depth
25 in/min cut rate
.2 in deep tabs

After fussing with getting the starting point picked (more on that later) I hit go and the M2 went to work.

My actual questions:

The head speed was likely too fast as the router struggled with the material and it left an almost scalloped edge on many of the pieces. What is the appropriate head speed folks are using for a .2in depth cut and a 1/4 in bit?

The cuts in some parts are verging on perfect (my test piece for example), smooth and they fit well. Others are stepped, almost terraced, where the bit moved 1/32-1/16 of an inch UP on each pass. Removing more material from the bottom of a part that was already properly sized and leaving a step down on the upper portion of the part - a very nasty edge.

Also my part sizing is vastly different from one side of the layout to the other. Talking almost a half inch in length on a part.

So… what additional calibration tips are out there? Better recommended cutting settings? Is it possible to do cut furniture with slots and tabs with an M2 or is this just the wrong machine for the task?

All advice is appreciated - Z