WireWolf wrote:

Frankly the only thing that personally comes to mind is religious stuff. 

That would be an interesting idea, though refining the diplomacy system might be another good option. I would also like the Mezari fleshed out a little into their own faction, maybe even get their own faction quest. However, I very much doubt we will be seeing any further major updates to the game. I don't think they are strictly necessary either, since everything of significance that was lacking has been covered already.

Expansions are usually motivated out of a need or a means of introducing new gameplay mechanics to help fill out what's not currently there.
Guardians introduced Wonders.
Shadows introduced an espionage mechanic.
Shifters refined the winter mechanic and now Tempest is adding in further refinements to the games oceans.
Any other expansion to Endless Legend would have to introduce a mechanic that either isn't present in EL or is very barebones.

Frankly the only thing that personally comes to mind is religious stuff. 

KnightofPhoenix wrote:

I find it highly unlikely that we'll get a full blown expansion after Tempest, as EL is more or less complete now. At most, we'll get small DLC like lost tales and a balance update.

So, what then? EL2? :D

I find it highly unlikely that we'll get a full blown expansion after Tempest, as EL is more or less complete now. At most, we'll get small DLC like lost tales and a balance update.

I hope there is another one after Tempest... after all they can't just quit with 11 factions. There is still 1 slot for a 12th one! ;)