I just noticed that nobody's updated the HB template in a long time, and there are several former-villian turned-heroes via lockboxes that do not link correctly to the hero page. These heroes include:
Thane does not have a enemy/boss page, and Doctor Doom's enemy/boss page is named "Dr. Doom", so these are the only three that currently need to be added.
Turns out it's less difficult than I thought. I just needed to browse to the Template:HB page, click the Edit button, and add the above three heroes to the two switch/case lists. The only slightly tricky one was Taskmaster, who had to replace Satana as the last name on the list, and so needs to be on the same line as the equal sign.
Ok. Looks good and I didn't break anything.