Prior promos have actually been pretty good value in terms of money to credit value, especially the big sale and phylacteries. This current one is bad in comparison, because it 'just' offers the same tradein value as you'd get buying credits.
I feel like the horde could do with more expansion - They used to often just use class skills, be skinned as "Blah Mage", and we've not seen new varieties of horde in a while, or any indication about the various clans/groups that exist within them.
Which makes me wonder: Might we see differentiation in kinds of horde? Subfactions within the horde, with clear behavioural/attack/tactical differences?
The thing with undead pets and zombies is that there's so much IC precedent for them being dangerous, there's so much history built up around them in game that it's strange for most characters to tolerate them. Just because you know it's not harmful mechanically (yet) doesn't mean the IC danger isn't there.
You say being nitpicky about pets and that sort of thing pushes people away, but so does disregarding more than a decade of roleplay and lore just because people want a certain pet, buff, costume etc. If you want to play with undead things, fine - just don't get upset when characters with good reason to react badly do so.
An item that lets a character raise zombies is a little different to a bashing area though. One is characters using necromancy in orgs that have really good reasons to oppose that, the other is unaffiliated NPCs to hunt.
But yeah, reskins are probably the answer. Make the costume raise clay golems instead, or something. Not sure how to explain the need to feed corpses to it then, though.