1. Details
Enable the possibility for antags assigned at random rather than an admin. This should be a low chance to happen. Maybe 33% of all shifts.
Naturally some antags aren't fit for station, but that's mostly a question about changing objectives to encourage scenes and roleplay rather than just powergaming and winning.
Actions committed by characters as antags are considered strictly non-canon. Characters may remember a stressful situation, but only details about overcoming the hardship rather than "character X did a bad, fire them!"
Antags would come in two categories, ones actually disruptive enough to rile up the station population in general. And ones that are just supposed to discretely complete a minor objective, such as eating someone for knowledge. Encouraged to pick someone interesting, bargain, persuade, or ambush to complete this objective.
No need to code much, just tweak existing roles.
2. Arguments
Argument 1: player incentive and rewards.
Right now the station to me is incredibly dull. We have departments, we have jobs and mechanics, but we have little incentive to actually do these jobs. Medical might spend an hour making chemicals that won't ever be used. Security might not even bother to gear up because criminals and actual threats are far and wide between. Social jobs like the chef, chaplain or bartender rarely have relevance in stressful situations either. Whilst on other servers they are often the main answer to a specific threat.
I understand there's a belief to create a mild environment where people can freely engage in voracious roleplay. But then that begs the question, why play at all? If you're only going to log on to scene, or observe people eating one another as a ghost... you might as well go use a chatroom. Vore-station is still space station 13. It's still a game. There should be reasons to play other than text-based scenes alone. A harmony between mechanics and roleplay.
Even if we don't have an antag every round, antags are a great way to offer an incentive for players to play. The mere notion of a possible threat makes it more prudent for people to make the ooc decision to prepare for it. And when a threat actually happens? Well, people bond together to defeat it. They forge memories, friendships. A reason to come back and play more. A reason to opt for a game, and not a roleplay chat or forum. Yes, a lot of players might find events too disruptive, but if they're here for the space roleplay aspect, the dorms are a protected environment where you can vore to heart's content. If people feel like they did good by preparing for something bad, they feel rewarded.
Argument 2: We don't have to follow the classic SS13 antag formula.
We're a vore community after all. So who says that objectives can't be more ambiguous, antags can't be voracious aliens? Perhaps someone is tasked with merely encouraging vore in a certain way. Having to cause mischief without being caught, expected to pin it on some gullible prey instead? Corrupt officers making up crimes? Crazy scientist transforming preds into monsters, or simply creating them? Chaplain offering sacrifices to a voracious entity beyond? Engineers creating contraptions simply to get crew covered in scrumptious, tasty syrup. To trap them for collection and consumption later? Could even be a prey capturing a pred for their obsession. We already have a lot of tools that can make these kinds of situations possible in the code, players are just discouraged to use them like this. Often times because of preferences. But we're a vore server? You don't have to do a hyper detailed ERP super roleplay, just getting mechanically eaten and contributing to the story is plenty already.
Argument 3: Don't avoid something just because it might cause problem on occasion.
Yes, antags can cause problems. Sometimes people might misinterpret their objectives. Powergame rather than roleplay. Prefs might get misunderstood. But just omitting antagonists entirely because of possible issues? That's just ruling out a fun roleplay mechanic entirely. Antags are a learning experience for the community. Take security for example. There's few people who play the role of officer the intended way right away. You'll get a lot of shitters, and people get angry. But we still have security. We consider them a valuable enough assets due to the opportunity for belly brigging and more. Antags present a similar opportunity, if handled correctly.
Argument 4: You can't rely on players alone to spice up the round.
Due to the static nature of the game. (each round happens pretty much the same. You'll always have all the departments, at worst a few grubs might show up, and really rarely, a meteor might hit the station). Creative players might create interesting situations at first, pro actively seek out roleplay and partners, but after a while folks get burnt out. There's only so much you can do as a player with the tools given. And moreover, pretty much everyone can access the same tools. So players fall into a routine. They do the same jobs, the same stuff over and over. They run out of ideas, and being used to the station as they are, the novelty has run down too much to give them inspiration. Less and less people stick around, people go play elsewhere for a new and exciting experience.
Think about it. Knowing there's an event or experiencing something unique on a server gives players more of a reason to open that discord, to connect with the community, and play more on the server.