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First, your dealer's working from a broken spec - it's not
-0.09 to -0.1 deg of negative front camber - it's -0.9 to -0.1 degrees with -0.5 degrees being perfect. So your front camber is ~perfect
Second, you can't do anything to adjust the camber on the F30 aside from buying new parts (oem swivel bearing for + or - 0.5 deg, or an aftermarket camber plate). Adjusting ride hight with different springs will modify the camber a bit (lower will add more negative camber up to a point) but not much - seeing ~-0.6 with m-perf springs seems right on what I would expect.
Rear camber is adjustable, the target from the manual is -105' which is -1.75 degrees. With the M-Perf, they might want a little more. -1.9 in the back isn't out of line - it will cause the rear to stick a little more in a hard turn (I put my rears at -2.0)
On to toe - normally all BMW's have negative toe both in the front and back - it leads to high levels of straight line stability at high speeds (think autobahn) and in the front, a heavy German steering feel at the expense of tire wear. Also the rear toe should always be higher than the front toe for the sake of stability.
The F30's specs for total toe are 14' in the front and 18' in the back (that means 0.23 degrees in the front and 0.3 in the back - total toe)
Also, when you see toe without an "in" or "out" associated with it - we're talking about toe in (i.e. the front of the tires are pointed at each other - cross-eyed). Toe out (front of the tires pointed away from each other) is sometimes represented as toe with a negative value.
Now, on to your seat of the pants feel that you don't like. You'll have to explain "turn-in is a ton more difficult as it's trying hard to unwind". Do you mean the steering wheel requires more effort to turn it and it loads up more (gets even heavier) with higher steering angles than before? If so that doesn't make any sense from your before/after alignment sheets.
You've decreased total toe on the front axel - that should decrease straight line stability and work against the camber thrust which should make the steering feel lighter. The car should also change direction quicker.
Now, if you came from a stock suspension and jumped to an M-Perf suspension steering input is going to be heavier, by quite a bit. Reason being stock suspension has a front camber of -0.3, half that of your M-Perf - meaning the M-Perf suspension has twice the camber thrust of the stock suspension. If you don't like that and want the steering to be lighter, your alignment tech is doing the right thing by decreasing the front total toe. It can continue to be decreased to lighten the steering, even going past 0 toe into negative numbers (toe out) as less toe works against camber thrust, up to the point where camber thrust is negated by toe out and the wheel has no self-centering ability. I'm not suggesting this as the car would be approaching un-drivable at that point.
I run my front with a slightly toe out configuration (i.e. past 0 toe, the fronts of the wheels are no longer pointing towards each other, but away from each other). This aids in the car's ability to quickly change direction (i.e. works well in the slalom) but sacrifices high-speed stability (i.e. car has more of a tendency to wander on the freeway).
So, in conclusion, I see no problem with the current alignment on the car - it looks mostly normal with a little less front and rear toe than manufacturer spec.
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