With #17, it didn't bother me that a lot of it focuses on the heroes trying to get everyone on the Mosaic free, since while they could have definitely sped it up, the ideas as presented in the story were interesting enough that it kept me engrossed; especially since the whole last issue was the heroes just standing around and, from her perspective, talking down to her, we did kind-of need to see them realize that this isn't a pure, black and white situation.
Definitely agree about wanting to see Hamner complete this series--the artists that do these two issues aren't terrible at all and do a fairly good job with it, but that would have been amazing to see.
There was something I noticed art-wise--Katma Tui's costume by #17-18 is the same one that John was wearing at the beginning of the series. I have to imagine that was on purpose.
As for John's "Master Builder" retcon...it is sudden, but I think Jones explained it well enough that it made sense.
I'd love to see that first issue as a one-man play too.
Good episode, and good series for this, erm, series.