A lot. Getting resources early is huge, and wiping out the enemies is also nice...

Economy starbases are more subjective. It sort of comes down to your settings, and how you build up your planets. If you play abundant with tight, or even loose clusters eco starbases can give serious bonuses. Ex, pick a tight cluster of 6 to 8 planets, build all research on them and stack as many eco-starbases on them as you can. (production is good as well)

The problem with this is at higher levels, it gets harder to balance this. If I try to do this, I ussually over do it and don't have much of a military and the AI jumps on me. (can ussually beat them back, but it's slow going)

For me I find it better to just try to gooble up the resources, build them up, then build up militarily, then slowly start building eco-starbases in key places. Later in the game, I end up building primarily constructors. Which end up either being influence or eco bases.

The thing to remember is you really don't need a huge military. (just need a potent force) This is especially true once you have 2 or 3 military resources maxed out. It gets wastefull to keep building attack craft, so I just build tons of constructors.

EDIT. Off resource only gives research/production/trade or influence bonuses.
On resource, gives whatever that resource is. They're all pretty good, for me the military resource ones are the key to getting control of the game.

Economy starbases are a nice edge to have.

Influence starbases are only worth it if you can get the Influence bonus over 100%. With the cultural conquest modules alone, you can push it to 255 at max. Its not easy to predict how long it will take a planet to flip, they've made the Influence system a lot more behind the scenes than it was in GC1 when you could check influence rating by sector, but you can typically be assured a planet will flip within 10-20 turns of being put into crisis mode. Even less if one of your planets is in the area of effect for the Influence base. The lower a planet's PQ and population, the faster it will fall. One game I actually took out three alien homeworlds first by planting a trio of Influence bases with the Cultural Domination line. Toria IV collapsed quickly, while Thala, Arcea and Toria took a LONG time, easily 15 turns (I wasn't keeping absolutely careful track, Thala was the longest to hold out).

As far as I'm concerned, the Diplomatic Outpost tree of the Influence starbase line is useless. The bonus levels next to the Cultural Domination line are next to nothing, and combining the two is a waste of constructors. If it comes to needing that kind of Influential firepower, you're better off with two Cultural Domination bases than a single Influence base with both lines installed.

There is a notable improvement, even with only one or two bases. I don't usually go to the extreme of 16 starbases on one planet, but its not unusual to put 2-3 overlapping around my homeworld and the core worlds of my empire, and even then, it IS nearly a doubling effect. The best place for them, in my opinion, if you're just upgrading the trade lines, is at the furthest point you can put them in your empire along the path of travel. The further a freighter is from the planet in your empire it originate from, the more its generating.

Theoretically, the best place would be an economy base at the destination, which is the peak production point. Most major AI empires have issues with this, but it does explain why the minor races tend to plant economy bases near your homeworld when they start trading with you.

You can build a trade route with econ starbases, and only upgrade the trade module. Takes 4 constructors, giving a 60% boost to frieghter income along the route. Works while at peace. Placing starbases in the territory of another race, can be tricky, and I have found if I put it near a star that is not inhabitated, then they do not get upset, and I get the trade income boost as the frighter passes through.

so I'll planning to try a string of starbases along the route, to see what that does to my monthly income.

I've seen people do this although I haven't tried it myself. I've seen someone get 9000 bc a week from a single trade route, but he had starbases all along the path and there were a *lot* of them. They are also a major target in a war and if they're spread out along the trade route, which is the most effective way to increase your trade income, they're difficult to defend.

I tend to use economic SB arrays around my major research and production planets filled with manufacturing modules. I don't bother with the trade modules at all, because I've never bothered with trade. With the 16 SB's that DethAdder mentioned, you get close to a 400% production and research bonus on every tile on every planet in the SB influence area. Getting 8000 RP's of research per turn from a single planet or being able to build a 4000 bc battleship in 2 or 3 turns on 3 or 4 planets is huge.

Nobody has been talking about miltary starbases. Eco are nice, but military are great!!

No they r crap...no offence but they have a huge flaw, they can't move. To a newbie player they r great but to a experienced old hack (at GC2 anyway), they r a waste of resources. Get dreadnoughts/battleships instead, much more fun. U will win much quicker as well...

I've

This should be I have  

Use of SBs like the top image can lead to production like the bottom image.

Use of SBs like the top image can lead to production like the bottom image

That is pretty amazing. This appears to be DA. I don't think you could get 20K on DL with only 16 econ SB's and what appears to be your tech capital. Is that a Bank or is it something else? Something intrinsic to DA must be going on here. Any idea what it is?

I guess you could just have a lot of research resource mining. When I had 11K, I only had 3 research resources plus I wasn't neutral. So I suppose 20K makes sense if you're neutral and have at least 5 research resources.

After looking closer the planet is at 109 IP so it's it's the McDonalds all right.

I didn't see anything to indicate it as a DA game. Those type of bonus tile frequencies just aren't happening in DA.

Yea the pop changes were done in 1.4, and have stayed the same for DA. Farms only get you three Bil. now and tech increases by 1Bil.