I think it would be great if there were a way to link Expression control and the Vel XF control with an adjustable ratio (like Audiobro does with Modern Scoring Strings) so that you can control both parameters at the same time with only one CC/physical adjustment of the modwheel or whatever else you use to control your expression and dynamics.

I've found it super useful in Modern Scoring Strings both for performing and for programming in manually (which I do often as I'm a limited pianist/keyboardist) to have the one lane of automation controlling both the dynamics (Vel.XF) and the expression at a definable ratio.

Audiobro have done it well with just a button to enable/disable the linking of the 2 parameters, and then a dial to increase or decrease the parity between the 2. So with the dial all the way up, there's a 1:1 relationship. Every amount you move/adjust the dynamics, the expression moves the same amount. With the dial at the lower side, the Expression only reacts a little for each dynamics adjustment you make - which I think is probably how most people use it, myself included.

This feature would be so great in Synchron Player and it doesn't seem like it would be a difficult thing to add in.