Why Joxer and Gabrielle?
Aside from the focus of the show on the two characters during Xena's pregnancy (and lessened screen-time), I personally always found their relationship intriguing. The changes that Joxer put himself through, with Gabrielle as his inspiration, sort of moved me... Joxer was really undeniably irritating in his earliest appearances, but after falling for Gabrielle one could see him really trying. It's not recognized in a lot of circles, but the character really went through a huge development starting in season three. Unfortunately, due to differing writers and a lack of a cohesive vision about the character's direction, Joxer's growth often tended to be one step forward - for example, Convert - and two steps back, such as - well, pretty much any of his other appearances in season four. :P
As for Gabrielle, I felt that what Joxer could bring to her life - if she'd let him - could only benefit her. He needed her encouragement to become the great things he could, but she needed him as well, I thought. Gabby had been my favourite character during seasons two and three, but beginning in season four I started seeing the effect of her life with Xena as being darker and heavier than she deserved. By the end of that season I found it hard to like her at all anymore; I really thought that she - and Xena too, in fact - could just stand to lighten up somewhat. When Joxer was around, they seemed to do that. (And in season five, Xena seemed like she REALLY lightened up around Joxer, which was cool; Gab on the other hand seemed to close down even more, though I can't really blame her *g*.)
So, in any case, that's why. I found the growth patterns of both characters to be really interesting, and more than that, I found the potential for growth between the two of them even more interesting. I was disappointed when, at the end of season five, most of that potential was pretty much smashed *sniffle* But I have my memories. ^_^