Nullable Fields to Separate Table?
Rather than stick with that table, would creating a question table work for your application? That is, instead of having a separate table for each question, have a question table as

CREATE TABLE question (question_id numeric, question text)


and instead of the AFE table linking to a bunch of other tables, create a separate answers table as 

CREATE TABLE answers(question_id numeric, afe_id numeric, answer text)


That acts as a bridge between AFE and question. This lets you add new questions easier too.