Having a quick play with the exciter for the first time as been sent a couple of tracks seriously lacking about about 7kHz but are good apart from that. I know you can’t polish a turd but thought it some material to see how nicely it can work when really needed.
But one thing I have noticed is that switching the Band Mode between Stereo and Mid/Side changes the sound very extensively. EG the Crisp preset looses all the top end which has been enhanced when switching.
It seems a setting of both Mid and Side set to what the Stereo sliders were set to keeps the sound at least approximately the same (which should make sense as stereo should effect both mid and side by the same amount.)
I don’t know if you’d want to gang the sliders in some way overall but at least for the Presets packaged with Renoise I feel they should be saved so there is minimal change in sound when changing this setting.