I mean, the FEC line is so limited that I do think there's room for even new infantry heroes. For example, I wouldn't mind a court mage style ghoul courtier, and I don't mind the recent campaign harbinger. I would prefer if these more specific type heroes replace some of the more generic heroes we've had so far rather than being in addition to them, though. If we have a ghoul messenger/herald and get a ghoul court wizard/vizier then do we still want or need just a generic ghoul hero courtier with no particular flavor to it at all? If I had my way, they would re-name the unit champs of ghouls, horrors, and flayers to be 'courtiers', tell you that your converted and/or just differently painted guys are unit champs instead of heroes now, and replace all of those with new heroes that have more detailed roles and lore and actual bespoke models.
What I don't want to see is another Abhorrant Ghoul King / Abhorrant Archregent situation where there's really no difference in aesthetic or lore between them, ones just 'the same but a little more powerful' or whatever. That's garbage, imo. Similar to the courtiers, if I had my way 'abhorrant archregent' would be removed altogether and the model would just be 'Abhorrant Ghoul King on Foot', with rules closer to what the Archregent's rules currently are, and use the space that frees up for more stuff like this new gorewarden who potentially has an actually distinct battlefield role and some interesting and unique lore behind him.