So, after reading too much KotDT will do that to you), I got my hands on the new HM Players Handbook (and Hacklopedia of Beasts). While DCC and HM are very different games, they do have a few things in common, including an old school ethic and the idea of PCs starting at 1st as pretty much normal and clawing their way up.
The combat examples and rules really hooked me on the idea of going with a active defense roll instead of static ACs. I substituted in a d20 + Defense Bonus as part of yesterday's games; defenders (PC and NPC alike) needed to roll that and beat the attackers rolls to avoid being hit. Unlike HM, I did not add a default -4 to the roll; DCC is tough enough
It was a lot of fun. The players seems to enjoy it; it was a little more engaging, and they got a few more hits than they would have otherwise gotten (and possibly a few more misses, but those don't seem to have stuck as much).
The campaign is a tough one - lots of undead, demons and nasty stuff - so the active rolls should help a little. As static, the monsters are likely to hit more often I'm thinking.
HM also does an interesting thing with the dice scale on initiative. The die type changes with level of surprise, and their countdown starts at 1 (so, low rolls go first). Ambushers get a "1". Really surprised - d20 (which still give you a chance to reaction). Other options range between depending on how wary a PC was being, for instance.