2 quick questions.

I'm trying really hard to keep backwards compatibility in the model.ini file. Currently you can use an old model.ini file with current firmware, and I'll do my best to keep it this way. There are a few quirks (like the safety feature isn't set to 'auto' in old model files).

The Devo protocol was also reverse engineered, but not in precisely the same way as DSM has been. I'm not going to make claims of reliability, but in my opinion, it is the most stable of the supported protocols. Lots of folks here have been flying 4 and 6 channel helis using the Devo protocol.

The WK2801 is in pretty good shape. Im not aware of any issues with it currently.

The WK2601 protocol still has real issues, and probably isn't really ready to use.

There is swasplate mixing.
Try to apply the 6ch heli template to a new model to see how it looks like.
Click on helicopter on the model config page to select the CCPM type...

BTW I doubt the 2702 needs it...

You can set those limits at the channel 1, 2, and 6 config's scale value, to which the cyclic 1, 2 and 3 are assigned.

I need to understand better how to implement what you need.

today we calculate a 120 swash via:If I understand the swashmix properly, it would instead do (for instance)you should be able to get a very similar result by changing the scale on the virt1,2,3 channels

However, for fine tuning, that is probably pretty annoying (you'd need to go back and forth between several pages), so adding the ability to directly control the swashmix in one place may make sense. Still I'd want to understand if the above approach would actually do what you want it to.

Also, is there a requirement in a swashmix that the 3 values always add to a constant? I.e. if I increase the collective mix, is it required that either elevator or aileron mix decreases, or can the sum be > 180%?

I still got the feeling, that you are always talking about scale on the mixer pages, while we are talking about the final scale value at the channel properties, which should be set once, and you would still have your curves at 100%.

So I was talking about this: model menu -> click "1-ELE" -> scale (one before last).

PB was rerefering to this too on the virtual channels, which do not have this option yet, but if they would have, that would be identical in function to your swash mix values...

Yep, that's why PB talked about the scaling the virtual channels...

At the moment your only way is to define one more last complex page to the virtual channels, make it a multiplying one, and set the function to fixed with some value less then or equal to 100%. However this way you can only reduce the channel's value to set the proportions...