I'll guess, that you already know, that you can use shortcut [Drum] + [Mute] to mute individuial drums,...
...they could implement it through midi with some external buttons (would be kinda usefull),
but your second request is just about switching the regular function of device. (and that could be thought bit more complex)
i would rather have possibility to toggle to separate drum muting mode:
(for example [shift] + [mute] would enable a mode, where you will with press of [drum] + [mute]:
-enter direct tap mute mode, in that: you could directly tap an pad which would mute it / un-mute it.
-pressing (and releasing) of [mute] alone with some individually muted pads already active would act as nowadays and it would reset the mute of all...
[drum] + [mute] again for sequencing as usual.
[shift]+[mute] again for default ( [drum] + [mute] + [pad1-16] ) behavior. )