Sounds like a good idea: now that you mentioned it I remember having staffing issues on small planets so not having the additional slots shouldn't mostly make any difference

Question is: how does the player know on which planets they got a new slot?
Maybe via a notification listing the planets names with hyperlinks?

Hi sven! Loving the diplomatic improvements in Steam's dev branch.

I add all the slots I can then terraform the planet for more pop. That also usually adds more slots.

The tedious amount of clicking is caused by the queue fillers. The +1 slot techs are fun and simple as they are. Your proposed change doesn't sound intuitive.

Noticed I have to add/remove queue fillers while waiting for pop to grow. End up periodically checking many of my planets to see if a slot has appeared.

Finally getting access to a few million of a new race is just about as good as a +1 slot tech. It just happens over more turns. Not having aquatic or subterranean races available is definitely a hindrance.

These issues (intuitive and rechecking) can be resolved either by a notification listing the planets with additional slots and hyperlinks to the build menu of each planet OR: by an icon displayed next to the planet in the production list

Since the additional slots would only affect large planets which are a small portion of all planets, identification in either method should be simple: one could even sort planets by the amount of free building slots available or if they have any at all, or by sorting them in descending pop order and checking the top few which obviously make the biggest impact if they get new slots

Good idea, sven. That tech does run counter to the design as it stands; your tweak makes it cleaner.

The latest dev build seems to have this change to the second +1 build slot tech. Only applies to planets over a certain population amount.