The whole point of the trust being irrevocable is to prevent outside parties from being able to force the trustees to give up the trust’s assets to satisfy personal liabilities. Once you have clearly understood this, you would cease to ask that question. You would want the trust to be irrevocable 100%. No, it is in your interest for there to be no exceptions.
But as I said before, the managing trustee can put assets into the trust and can take assets out. Just because the trust is irrevocable doesn’t mean you can’t take assets out. So if that’s what you were worried about, put that worry to rest. You as managing trustee can put assets in and take assets out at your discretion. And by the trust being irrevocable, no outside party can force you to take assets out to satisfy any kind of claim against you personally.