What exactly is "reckless expansion"?

[Zaimat]

hmm. Since this effects diplomacy, I would like to suggest that you adjust this based on the difficulty setting of the current game.

Yes, I've been considering this but this might already be permissive enough after the adjustment made that it's effect is lessened. Need to see how it plays out first.

Another suggestion I have on this is to allow the human player to threaten the AI players in the same way, and while I'm thinking about it, I rarely seen the AI colonize A planet in the same sector as someone else unless they are allies (the AI does not appear to do any sort of wreckless expansion at all even though some of them are suppose to have aggressive tendencies)

The option is available under threats during diplomacy if the said race meets the criteria of reckless expansion (and others), the list is dynamic. As for the AI races, it's possible for them to expand recklessly if they are doing well, and the AI races do complain to each other just like vs. the player but you are correct that they won't colonize planets in others systems.

[Xyquas]

The reckless expansion (controversy) is based on how much a race has expanded within the last 10 turns. If it's greater than the set threshold then other races may complain via diplomacy (only once every 10 turns). There is a minor tolerance hit if they complain.

Expansion is calculated by the amount of your race's presence in new sectors/systems. Owning one or more planets in the same system counts as One.

Looks like the threshold is pretty harsh so I'll adjust it to be more permissive. Right now if you gain presence in 2 new sectors within 10 turns, it is considered reckless expansion.
I'm thinking I'll change it to something along the 3 new sectors within 5-6 turns. What do you guys think? What would you consider too fast an expansion rate for your play style?

I never felt this being too harsh but I agree with keller to make this setting depending on chosen game difficulty (if it isn't already). I'm playing on normal difficulty.