[DirectorTsaarx]

Magus: I don't know what the "Effect Value" does. I do know that, at least through 1.27, one Counter-Intelligence project (of any level) could counter only one Intel project (of any level).

The "superiority" of the levels is mainly that the higher-level projects are "active" for a longer time, so fewer counter-intelligence points are wasted on CI projects that don't counter anything. Of course, there's also one Intel project that can't be blocked by a level 1 Counter-Intel project: Research Stealing (or something like that; the one you can use to "copy" another empire's research and gain a level in some research area). It's a high-cost (like 150,000 points) project, so you need a Level 2 Counter-Intel to stop it. But it's a fairly benign project - you don't lose anything if the enemy uses it on you; he just gains a minor tech boost. Which the AI may or may not be able to use...

As for having 20 enemies: you're in trouble. Run 12 Counter-Intel projects, build LOTS of Intel Facilities (so you can pump lots of points into each project every turn) and hope for the best.