Vertex Groupe must have pass index like layers and materials in grease pencil objects

hi, when we want do add Modifier and affect many Vertex Groupe at once to we have to create a new vertex groupe contain them then add the new vertex Group to the infuence modifier. but its limited if we want to not efeect after that some of them.
so my idea is to add to vertex group "Pass index " for every vertex groupe in order to have the ability to specify a set of vertex goupe and also animate the Pass index ... * as we have for layers and material......