Conditionals that set field values - not just make them visible

It would be very helpful to have conditionals that allow for the setting of other field values based on a single field value.

Example - I choose a State, based on that I want to update 3 custom fields that indicate the State Agent, State Funding, and State Form Required.

I can do this with a trigger AFTER the ticket is submitted but it would be very helpful to be able to have this happen as the form is being filled out.  Especially on the Agent side.