I think I may well have read Time and Mr. Bass first, as it was the only one we owned. Boy, did Narrow Brain freak me out when I was seven or eight.

Apparently Eleanor Cameron was still working on another Mr. Bass book when she died, according to a comment on Mari Ness's review of TAMB at Tor (note: she did NOT like the book at all): http://www.tor.com/blogs/2014/06/sometimes-abandonment-is-better-time-and-mr-bass