The Intel system of SE4 is horribly, horribly broken, as following:
Intel attacks are either horribly overwhelming, or impossible to get anything through the CI of the targets. A situation in which both sides can get some projects through, but some others are blocked, is almost never a possibility.
If a mission is not blocked by CI, it succeeds 100% (except for PPP, but that is only 1 mission). This is wholely unrealistic, and only compounds the all or nothing problems of SE4 Intel.
You have absolutely no possibility of defense unless you research Intel and devote huge amounts of facility slots to it. There should be some minimum generation per planet or something for intel that can only be used for CI, so you are not completely vulnerable. Even the Intel you can get from Partnerships is nowhere near enough to provide effective defense from a dedicated attacker.
All of this stems from a poorly designed system. Some would argue that removing Intel removes some possible strategic actions. This would be a good argument, if the system was not horribly horribly bad.
These problems (except the low level of Intel generation, maybe add 50 or so Intel Point Generation to Research Centers) can not be fixed by mods; they require hard code changes to fix.
So, I still would prefer that Intel be disabled for this game. I welcome all arguments, criticisms etc. I am sure I can come up with more reasons why Intel should be disabled if you want me to.