adding a level parameter for the output of a module in every module would be a bad idea, it would just clutter up all the modules. a seperate mixer module might make more sense here, but from your explanation it seems you are looking for something different.
on the recorder page you use the up/down arrows to step through the input or output channels and you use the SwRec button to switch from input to output recorder and back. so you can see what you are going to record, but it’s true there is no true “level” display, like vertical bars on a mixer, if that is what you had in mind. doing that would mean the entire UI of the recorder would have to change, so the waveform display of what you are actually recording or have recorded, or the file you have loaded, would have to move somewhere else.