Who can run Extreme for a month? Extreme is over 4x my current income, and I don't think I have a bad economy. I make $67k/hour at 2200 acres. The point is that you CAN'T run Extreme for a month, and so it would discourage running Extreme for short periods, because you'd lose your "Active" bonus.
I'm not saying my suggestion is great ... it was just something I came up with off the top of my head to maybe get discussion rolling. I'm not in love with it, and I'm sure it has flaws. But your suggestion of getting rid of science because it's "overpowered" is much, much worse.