A few options here:
— the VCA with CV envelope open/closing it can generally be last in the chain. That way you just have one lane of VCA managing all related needs
— you COULD if desired send a dummy/nul channel to your sequence selector, that way you are sequencing in rests on an affirmative/positive basis

BTW sounds like the setup you are running has a lot in common with the Verbos Sequence Selector. There’s a bunch of Verbos videos for that online, those would be helpful and inspiring for you to take that technique further.

Cheers, Nicholas