Not resting on their laurels, Dev Diary #234 talks about future plans now that the Aquatics pack has launched:
https://forum.paradoxplaza.com/forum/developer-diary/stellaris-dev-diary-234-aquatics-and-3-2-are-out-now-what.1499640/Sounds like the main focus is now turning to the coming Unity rework, which is currently targeted for the 3.3 update due in February. The devs are considering having an open beta with the new changes so that they can incorporate player feedback into the update. If there is a beta, it will probably be launched around the end of the year/beginning of next year.
The devs have also begun exploring the possibility of adding a new "Situations" system, which would apparently work similarly to the Disasters system in EU4. It sounds like this would be rolled out more gradually over the course of multiple updates, however, as they don't wish to introduce too many major changes at once..
In terms of "buffing the backlog", the Custodians' next project is adding content to both Nemesis and Necroids. There are no specifics yet, however, and are in fact inviting community input on ideas for what might/should be added.
In addition, there's a ton more work planned for the AI. (Apparently, the improvements made in the recent 3.2 update have gone over fairly well.) I'm really happy with the effort that the Custodian team has been putting into this so far.
The dev diary also included the transcript from the recent Q&A session. I've posted some of the responses here (I found the bottom pair of Q&A's particularly interesting):
Q: Pleasure Seekers and Slaver Guilds seems like an obvious thematic combination, but you are not able to combine them. What is the reason for that and any chance that will change?
A: It has a lot to do with how living standards are handled in the game currently. They are done through code and are quite rigid, we are exploring solutions to it.
Q: With how consumer goods work now, they feel like nothing more butnan upkeept mechanism with no real value. They also kinda make amenities redundant, since they both have the same thematic function yet are separate resources. Are there plans to further divide their uses and perhaps make consumer goods more useful when in surplus?
A: I agree, and I'm not a huge fan of consumer goods. I'd love to be able to figure out a way to have repeat spending of consumer goods, to improve parts of your empire. For example, building research projects (similar to how you can spend to build ships, but that dont actually create entities like ships).
Q: did you think about buffing democracy and oligarchy to make it more equal in terms of strength when compared to their more authoritarian neighbours? Mandates are just too weak.
A: Yes the government types are quite boring right now and could do with a rework.
Q: Is there a reason Rogue Servitors aren't able to pacify Amoebas like xenophiles and pacifists can?
A: That sounds like an oversight, feel free to make a bug report about it!
Q: since we have locked Civics in the game. wouldn't it a great opportunity to add Ascension perks to them to improve on the them?
A: That and tradition trees are a good idea takes notes
Q: any ideas for spiritualists going foward?
A: With the unity rework we are working on internally it should hopefully be a lot more powerful.
Q: will gestalts ever be able to make anything else rather than a galactic union? Or is that always gonna be the case?
A: Rogue Servitors can form Hegemonies currently, and Machine Intelligences can form Research Cooperatives.
Internally we've discussed the possibility of providing other ways of opening up the other Federation types to all Empire types.
Q: What system will replace admin cap?
A: Admin Cap will be removed, and you will use Unity to upkeep for things like Edicts. You won't be able to avoid the penalty from sprawl, like it used to be. We'll have to balance the rubberbanding effects and should also add a game option for how harsh you want the penalty to be.
Q: Will the new colossus wipe out all life in the planet if fired on enemies, change the type of planet but keep the pops on there, or cant be fired on enemies?
A: The Deluge colossus will kill all non-Aquatic life on non-Oceanic planets when it terraforms the planet. It can be used on your own planets if purge is allowed. (Primitive planets can only be Deluged if you have full interference policies set.)