Tim, the tone mapping Leica does in-camera when creating the DNG is very different between the M10-M and M11-M. The best way I can describe it is as if they are two different film emulsions. Capture One uses the same "color profile" for both cameras, which is a misstep on C1's part. The M11-M needs a different tone curve (in C1) vs the M10-M. I suspect part of the difference is the sensor itself and a delta in the IR sensitivity. I can't prove that, just going on a gut-feeling.
The M10-M's files are more contrasty and I get more textures in the upper highlights. With the M11-M, the texture is there too, but seems somehow squashed into a narrower tonal range, so getting a micro contrast in this upper tones has been really tough me. But the M11-M does really smooth looking files, and they are insanely clean at base ISO. In some cases the M11-M's overall tone curve works. But like you, the M10-M "look" is my base line reference point, so the M11-M has been alot of "WTF" over the past 5-6 months.
With regards to filters, I use dark reds on the M10-M (that works well for me in the southern light). With the M11-M, I've been dialing that back to a red filter (#25). Not sure if that is helping or not.
