I think, something that would fit quite well into the Steampunk-Era setting would be a race for research. We could combine that with spicing up the future content-drops.

Basically, we would have a global deposit, that nations can pay Emeralds into, which will count as Research-Funds for said nation. When a certain thrashhold of funds is met, the content gets released, but at first only for the people who provided the most research-funds. Then, after a week, the second highest contributer gets the stuff, then the third, then everyone who funded and after 4-5 weeks a public release is made.

This would have several advantages:
-It would give nations with a strong economy a competitive advantage
-It would allow the Admins to beta-test and balance the stuff before it hits the wider server
-It would allow for nations to compete in ways that arnt wars
-It allows the Admins to space out their content drops in a way that is well-planned in advance and clearly understandable for the players.


Things we could lock behind such a techtree:
-Warships
-Armed Zeppelins
-Clues for powerful drinks
-Shotguns
-Improved Armor
-Improved Guns
-Improved Shells
-Upgraded Factories
-Certain new Factories
-Tanks
-Armored Vehicles
-Mines
-Potions and Food
-Smokable Receipies