1. Currently the War in Heaven creates a single large Federation for the Non-Aligned powers. This can result in the destruction of every federation that the "head" of the Non-Aligned Powers isn't a member of. This causes problems as-is (the destruction of federation fleets, diplomatic impact from leaving existing federations even between empires that both joined the Non-Aligned league, etc) and with more complex and differentiated federations that build out over time this impact will only increase.
How will the War in Heaven interact with the new Federation system? Will it be moved to no longer a federation, but (perhaps) a vote by the Galactic Senate, allowing existing Federations not to be torn apart?
2. Diplomatic options with Federations can be limited - no defensive pact is normal enough, but you cannot, for example, invite a federation into a war you are planning (or, at least, I couldn't last time attempted on this patch). Is this being addressed?
3. Federations can limit the diplomatic options of their members. How does this present itself to non-federation members in the case of (for example) commercial pacts? Is it possible to do diplomacy with federations as a whole, and vice versa - "united fronts", such as pooling the use of envoys and diplomatic favor in regards to issues, or decide on certain things (commercial pacts, etc) for all members at once?
4. There is a longstanding overflow bug handling relative power for diplomatic interactions; this can tear apart federations in certain cases. Has this bug been addressed, or will Federations continue to be vulnerable to sudden dissolution due to power imbalance?
5. Can federations interact with primitives in a specific manner? Currently new empires spawned from primitives cannot gain significant research boosting without becoming a vassal, but that's the sort of thing a Federation might take an interest in, for example.
6. The AI currently has its own ideas about what it should be constructing for the federation fleet. Will it be possible to (say) create a federation fleet setup in the Fleet Manager and have the AI follow that to fill in the fleet in concert with your planning (if you're the head) or have it be presented to you somehow for you to fill in (if you aren't the head) to keep it more coherent? Or some other way to influence how the AI builds ships for the fleet?
7. There is an issue where the Federation Fleet needs to be upgraded repeatedly to actually upgrade to the correct designs. Has this been addressed?
8. It is very easy for the Federation Naval Cap to be wasteful; with 3 empires each needs ~330 fleet capacity and the diplomacy tree and you've maxed out the contributions. Has the Federation Cap been changed in any way, particularly given the introduction of a Federation type organized specifically around the fleet?
9. For the Federation origin, the teaser image showed a possible situation where the Earth empire could box in one of the other empires. Will there be any changes to hyperlane generation for this origin to prevent situations where one empire will have no directions to expand in?