I think the appeal of Mac, the character, is that he was trying to be a hero despite not setting out with the intent to be one.  He was a scientist, and was forced to become a superhero to prevent his designs from ending up into the military's hands.

JB: the Snowbird to dinosaur thing, which happened in the first issue of the current series, really bothered me both due to the major mass increase she took on (isn't she supposed to only be able to take on or lose small amounts of mass- like to an arctic owl, bear, swarm of insects?) and that a dinosaur isn't as obviously a creature of the north like previous shifts have been. 

I really need to re-read this run!

As noted, I see it as a precursor to JBNM. There's a lot of read-between-the-lines and connect-the-dots stuff--like Snowbird's father later conjuring up Tundra, Sasquatch and Aurora sorta becoming f*** buddies off-panel, etc.

I really like the idea of each story being taken from each character's own imaginary series, too. Puck's reference to an encounter with the Brass Bishop being a nice example. Too bad that editorial footnote which tried to "explain" the reference was added in.

Yeah...and ironically, the events that set in motion his final fate in #12 made him even more interesting to me. He went from the reluctant scientist hero to being almost giddy with excitement at the prospect of being a "New York Superhero!" (even wondering if he would run into Spider-Man, etc.).

Reading the issue as a kid, I was sure until the very last page that Guardian would be ok and the final reveal would be that Snowbird had died. Such a great ending.