Currently there is no way to increase society levels, other than it going up once per turn (as long as you've played in the last 36 hours). I do plan to have other ways of increasing society level though -- mostly through things like foreign trade.
How about something that lowers population, but increases society level? "Rapid Society Development: Pump resources into rapidly developing technology for this society's planet, however many people refuse to move with the changes and will abandon the planet for a simpler life." That way if you're willing to endure a bit of hardship now, you can get to the society level you want sooner. The only problem might be integrating this with the current system of upgrades to stop abuse.
The cruiser is not the most cost effective unit in the game, according to my carefully thought out testing system, that would (arguably) be the Battleship. They also have a higher tendency towards catastrophic failure (meaning the outcome of cruiser battles swings widely in comparison to other types), due to their lower relative defensive strength. If you look at Planetary assault alone, they might be the best. They are a lot like cruisers in WWI -- fast, sleek, sexy, but unpredictable.
Did you test this with large amounts of units with balanced resource use? For example, I can get 100 Cruisers for the same Steel cost as 21 Battleships - other resources are in such abundance that it doesn't matter. I'm not sure on the exact calculations for large fleets vs small fleets, but I've been working with 1.5x smaller fleet is used. So that would be 31 Cruisers used, which makes it 434|124 (Cruisers) vs 420|189 (Battleships). Ok, Battleships have more defence, but the Cruisers can still easily destroy a large amount of those Battleships in a turn whilst having loads of Cruisers left for backup.
100 Cruisers isn't hard to save for, even for newer players. ~2 week's worth of resources from 1 max population planet. For many of us, we can get a couple of thousand Cruisers in 2 weeks, which would only be a few hundred Battleships. The battles would take a long time, but if I'm moving my ships around, reinforcing them with smaller fleets and decimating planets, I can do a lot more damage with my fleets of Cruisers than my opponent can with Battleships.
Still working on the trade system, which is also were the slowness comes in running the turn -- I'm removing a whole bunch of redundant queries, it should be quite a bit faster now. Should get it up in a night or two.
Sounds good!
