questions

Looking at the exp boosts ( I got 1 plat) why is mind reava 1 (75%) boost 18 points and mindreave 3 (25%) 113 points, while kodiacs 1 (150% ) is 18? I buy the 150 % boosts because it is more " cost effective"

Because the effects of those are in opposite with what you are comparing them to.

It's why they're in reverse order.

I think the confusion is that the Mindreave buff line is for exp reduction (the KEI buff line is for exp boosting) - you pay more to increase the reduction.