I'm not running a particularly new system - i7 quad core 3Ghz. I ran a 6 player, 24 planet game that lasted over 10 hours (divided out over a week or so - not all at once
) and it ran perfectly fine.
One thing I did find significantly improved my enjoyment of the game - I turned pirates off. As a mechanic, they have their place but they're not for me. I found them annoying me more than enhancing the enjoyment, so I disabled them and concentrated on taking on other AI factions.
Great game - I never played much of the addons before now - only vanilla SINS, so I'm enjoying all the new stuff like starbases, titans etc. Titans really do change the way you play the end game - especially when you encounter another player's!
I'm DarkMellie - not sure what you mean about "unweildy" - I had 18 planets all running at once with very few issues at all. The interface is pretty cool like that. For instance, there's absolutely no reason to zoom down to a planet/system to build ships or upgrade planets infrastructure example - just click on the planet from the strategic view and do your orders from there. No need to zoom in to select ships, either. If you're happy to move all ships in a system, just click the bar on the left side of the planet in the strategic view and it will automatically select all combat ships. In my game, I had a "front line" that I kept pushing forward with a large fleet attacking, capturing planets and then holding them while I build up their defences. The planets one or two back from this front line were just churning out new ships and I was constantly moving them up to join the front line fleet - all without zooming in at all. Pretty powerful and very fast when you get used to doing it.