"Anyone who has been through he falls chain and poet lakes have any particularly nice places they recommend checking along the way or notables (pictographs etc)."

there is an old portage trail along Chatterton Falls that makes for a nice hike - there are 5 or 6 falls along that section that you only see from that trial - there is a campsite at the upper end/Chatterton Lake and you could hike from there as well as from the bottom.  its well worth the hike, especially if you are going to fish below the falls.  From the bottom, the trial starts at the campsite closest to the falls - the trail is "river left" on the south bank of the river - I'd not do that trial for portaging, just for the hike - there is a better/recommended trail further south.  I've tried fishing the upper sections, but have not had any luck above Russell Lake.

Since you are going to be in Atikokan anyways, I'd be sure to get a copy of the falls detail map from the ranger station if your outfitter does not give you one.