You should not skip anything in REG. These CPA exams are a mile wide. Expect the AICPA to cover topics that you did not have in college, like estate tax. Also expect the AICPA not to extensively test subjects that everyone has to take in college, like individual tax.
Knowing ALL of the most complicated tax problems in corporate tax and estate taxe is a must. I thought that Becker did a very good job with business law. However, Becker left me confused on the complicated tax problems. Dr. Yaeger and Bob Monette with Bisk Hot Spots did a very, very good job explaing the most complicated tax problems.
I nailed these complicated tax problems on the REG exam. However, I only spent 5 days studying business law. The adaptive REG exam soon figured out that I was very weak in business law. Almost all of my questions in the third testlet were on business law! I did not expect to pass the REG exam, but I passed on the first try using Yaeger Home Study for tax. Go figure. I did not study 40% of the exam (business law).