One major problem I've located in the revocable living trust documents is this: They made the successor trustee both trustee and beneficiary.

This violates the The Law of Trusts which has existed for thousands of years. A trustee should NEVER benefit from his own financial decisions unless there are NO other beneficiaries. NEVER. Even then it is bad practice. Of course, law firms who create these bogus trusts will defend their malpractice to the death.