We are aware that there are some issues, and we are currently making some research on our Flight Model to improve takeoff flight mechanics and general longitudinal stability, but this is a huge work that takes time, so do not expect to see news about it soon.
I suggest you tune pitch axis with the following configuration, which is the configuration that some real C-101 pilots use when flying our simulation: Deadzone: 5, Saturation X: 100, Saturation Y: 85, Curvature: 30.
Regarding multicrew, it is much WIP yet, we are busy with other bugs now and then we will get back to it.