There is a ton of info in the trip reports section and other posts on the Beartrap to Iron part of your loop along the Beartrap River. That’s the only challenging section on your proposed route. I’ve pasted a link to a detailed trip report below…in particular see day three. I was up that way in June this year and the detailed report is accurate. Low water will definitely slow you down. Plan on 12+ hrs for getting from Iron to Beartrap Lake, especially if double portaging with a group of 6 or more (3 canoes).
As you may know most of the Beartrap River between a Iron and Beartrap Lake is in a PMA. You can pass through/explore the PMAs on a day trip without a permit but can’t spend the night without a date specific permit. This permit is in addition to the Entry Point permit.
Also, I take it your group is 9 or less and you are aware of the regulations on group size.
See day three