I have an AB revocable trust for the primary purpose of avoiding Illinois estate taxes. A large portion of the assets are in IRAs. I have the trust as primary beneficiary and spouse as contingent. The idea being that the IRA proceeds maybe needed to fund the bypass portion of the trust at the time of death of the first spouse. I have the spouse as contingent beneficiary. The thought is if the IRA funds are not needed for the bypass trust they could be disclaimed by the trust and then the spouse could get them to use the favorable spousal tax treatment. Two questions:

Would this work or would I be better to have the spouse as primary and trust as contingent?

If the trust accepts the IRA proceeds can they be added to a spousal IRA for RMD purposes or do they follow the 5 0r 10 year distribution rule? Thanks