I have a simple rule: if I am considering declaring, and I'm also nearing task saturation with whatever the issue is, I declare and then tell ATC to standby if I need to focus.
I LOVE that you are willing to show us all your mistakes to help all of us learn to become better pilots. It shows great character and humility. Thank you!
The best part about this whole experience, is that the ATC tries their best to serve pilots requests. This is why pilots shouldn't fear talking to the ATC.