Thanks for the comments. Upon seeing in other posts the many, varied ways people have adapted GTD context categories, I think the bottom line is one HAS to make the system work for them, and not worry that it is too much of a stray from GTD. I still embrace wholeheartedly the base and heart of GTD; I just find that contexts of @computer, @office, etc. all morph into one mess for me. Keeping my next actions lists separated by my major roles -- @research, @teaching, @service, @family, @supervisor, etc. works best for me.
Best regards to all,