I think First Nations is more the catch all? Aboriginal… has baggage? A lot of it seems to be who used to use the words previously? (I have no answers only questions!)
First Nations is a pretty new term, and has no negative associations (yet) so most people seemed pretty accepting of it? But I’m not First Nation, and my conversations were few and limited. I did have more than one person object to the term “aboriginal” but in the same conversation others said they didn’t mind it (and some self-identified as “Eskimo”) - its super complicated and emotionally charged and in general when I was having conversation with my contact in Nunavut I called her Maryanne. 
