Automated Triggers for Tasks in Multiple Projects

We’re implementing Asana for our team and I haven’t yet found a solution for our use case:

We’ll be using multiple projects per task. Each project will add its own subtasks in appropriate sections to keep tasks moving on time and add consistency for our team. Normally, we’d lean on “all subtasks completed” triggers to move a task from one section to another within a project - HOWEVER - with multiple projects moving at different paces, there will frequently be subtasks incomplete. I’d still like to automate a task moving from one section to the next to improve the team’s workflow. What might my options be for triggers? We’re already using a lot of custom fields that are completed via a form, so manually completing a custom field might be a frustrating extra step for team members.

Example:

Task: Campaign XYZ
Project 1/Section 1: adds 3 subtasks. When those subtasks are complete, Task should move to P1/S2 (P2/S1 subtask still open).
Project 2/Section 1: adds 1 subtask. When that subtask is complete, Task should move to P2/S2.

TL;DR: I think I’m +1 on all of the requests to be able to either trigger subtask approvals or build triggers based on specific subtasks or sets of subtasks.