Sort the account by what has to happen in a courthouse first
The most useful division in an immigration account is between matters that are purely federal and matters that need a state court step before anything federal moves.
Purely federal work behaves one way in an auction. Family petitions, naturalization, renewals: the intake is predictable, the fee is quotable, and geography barely matters beyond being able to meet the client.
Matters that start in a state court behave differently. When a case needs a predicate order, a cleaned up disposition or a guardianship, the state matters enormously, because a Jefferson County road and a Clark County road are not the same road. Those campaigns need their own copy, their own landing pages and their own qualifying questions.
Detained and deadline driven inquiries deserve a third bucket. They convert fast, they arrive at bad hours, and they need a phone number in the ad rather than a form. Do not let them share a budget with slow moving family work, because the slow work will lose every time.
Visa categories can be your ad groups. They should not be your account architecture.