Would creating a new 'Tremolo' palette item, for snare drum roll, be possible?

It seems any snare drum instrument I try, when it comes to applying a 'roll', the faster the roll, the more "over-triggered" sound it manifests... In the standard tremolo palette, '3-slashes' rolls are IMO slower than I like, and '4-slashes' rolls sound "over-triggered" to me.

If I can create new meters in the "Time Signatures" palette, could I create a sort of '3 1/2-slashes' new roll icon, that is halfway between '3-slashes' and '4-slashes'? Thx.