I agree that the current intel system could use some major improvement.
Please note that I never claimed intel was the best strategy only that it could be made into a viable one even with the current system taking into account the way most people view intel, as worthless. It would be interesting to see a combination of 3 or 4 players all with high intel working together intel wise to tear apart a stronger opponent.
As for 400k or 600k intel v 100k or 200k defensive intel
100k x 1.2 = 120k
120k x 2 = 240k
120k x 3 = 360k
200k x 1.2 = 240k
240k x 2 = 480k
240k x 3 = 720k
So the 200k intel person can block you out with lvl 3 CI. The 100k person will most likely defeat the 400k person but will find themselves in dire straights indeed if faced with the 600k intel on the attack.
And that is assuming level 3 CI. If you choose to give a little love to intel you will most likely be attacking them before they have that level developed, possibly before they have intel developed at all. Most people develop intel lvl 1 rather early for basic defense but nothing else in that tree until abit later.
Remember I never claimed this is a power game or even a good game or something to be done, only that it COULD be done (and has been done a few times in the past) with successful results, EVEN against a human. BUT surprise is always the most important factor here. If they know you are going to do it then it is easy to develop enough intel to block out the attacker. After the fact it will take longer to develop a sufficient intel force to block than it does for the other to break through even 4 fully developed CI 3 projects including accumulation of new defense point spending. IE: Assuming the defending continues to spend only in defense. Most people won't even notice that you are breaking through until you have taken out several CIs. By then it is far too late to act. After all you are only hitting with 4 intel projects a turn. Many just see the simple little blocked intel project message and don't even bother checking until it pops up several turns in a row. BECAUSE INTEL ISN'T A THREAT.
Once intel does break through a 100k defense it only takes 2 Tech espionages a turn to break any new buildup. Half the attacking points used at 150k x 2 leaving enough for an attack causing defender to break all treaties with their allies (large scale resource disruption and if ships are all locked together even combat scenarios of ally v ally, maybe a few glassed planets) at 20k for each of those with 300k to spend you can max out at 15 so a real total of 2 tech espionage to break 3 CI3 stored up in the event of counter attack and 6 treaties broken per turn with 180k leftover each turn for a new CI3. Once all treaties are down, even if quickly replaced the damage has been done. Now start with one turn of crew insurrections at 50k with 300k to spend that is 6 ships from the enemy in one turn. Negligable damage, unless you target a fleets minesweepers, supply ships, etc. It will also likely let you see into enemy systems and view their planets which allows you to specifically target the best most developed breathable ones next turn with 3 PPP or 6 Ground Contaminationsor a combination of them. -60 planet value in one turn or whole of the best planets switching sides. With this you can make large inroads into enemy production capacity in a short time. Take over crews to find targets and target the enemies strongest while taking over key vessels in the enemy fleets to prevent invasion. For smaller planets it is easy to bring the pop down to 0 with food contamination and totally eliminate their production. Depening on what the enemy has on their worlds anarchy Groups can also be devestating to planetary morale AND production. Insurrection on enemy mine layers and boom whole enemy fleets can be lost to prelayed mine fields.
With a large intel production base once you break through it is easy to crush the enemy in a matter of just a few turns with a well thought out strike plan. Many of the intel projects are quite devestating when taken as a directed group action.
So yes CI is very strong. But probably because it has to be in order to block the extremely strong intel projects. Most people even when they do get successful intel projects off aren't thinking about what they can do with it for maximum effect. They use it as something to harrass the enemy because INTEL ISN'T DANGEROUS.