Thanks for the input. I have read a bit more and I've learned what pigtailing means
Here's my initial plan based on my reading and the feedback on this thread:
1. Check all devices and connectors for AL compatibility
2. Check all devices for loose connector screws.
3. Check all marets for looseness and any signs of overheating.
I'll be back with more Q I'm sure based on what I find. I won't be doing any changes... strictly checking out and making notes on what I find. I'll likely get an electrician in as well depending on how complicated things get. Mine can't be the only house with AL wiring... I'm in a subdivision so chances are the neighbors likely in the same boat.
Thanks for all the suggestions. Much appreciated.