looks right to me
sound source -> signal in of vca, envelope -> cv in of vca, vca out to monitors (or wherever - mixere, processing etc)
nb I use signal in because vcas can also be used for cv and not just audio - modulate your modulation
a filter can go before or after the vca... whichever way sounds best for you in the current patch...
this is generally the concept of modular... generate a signal, do something to it, send it somewhere - try not to mix cv into the audio path (it's possible to damage speakers), apply modulation to things
see my signature for hints on how to get the most versatility in patching for the least expense
"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia
Utility modules are the dull polish that makes the shiny modules actually shine!!!
sound sources < sound modifiers < modulation sources < utilities