I knew both of my recommenders very well. (5 classes with one and 3 with the other) They both just wanted my resume and a list of the classes I had taken with them. I think it would have been different if they didn't know me as well.
I don't think you should add either, interests have no merit on a resume and like you said the GPA will be noted regardless. Unless you want to mention something like "Summa Cum Laude" or anything similar, then that's ok I think.
... put your GPA on the resume, especially if you have a ... at the end of the resume. Don't start listing a ... from the rest of your resume could potentially provide another aspect ...
1) Congrats!
2) Yeah, ETA is definitely employment (ridiculously fun employment, but still). I listed Fulbright under work experience on my resume and plan to list it under employment for LSAC apps.