Modernize XFA on evidence, not on a deadline
Classify every form by the runtime features it actually uses, and the migration waves organise themselves.
The blocker is rarely the layout
It is scripting, submit behaviour and dynamic subform logic. Measuring which forms depend on which features separates the ones that convert cleanly from the handful that need a decision.
A long tail you can see
In a typical estate around three quarters of forms are static layout or light calculation and convert without argument. The work is concentrated in a small remainder — but only if you know which forms those are.
Start with an estate assessment
Point YakForms at a copy of your repository. You get an inventory, a dependency graph and a validation report for the whole estate — before you commit to anything.