Wow; I am in a similar situation. They slashed our bonus structure into a pathetic shadow of what it once was, and jacked up our percentage goals. I will be extremely lucky if I git 80 percent this month (I work in collections; not really a collector per se, but a payment-arranger.) I am trying so hard to pull my weight, and I know that Mark does not flaw me for making less money than he does, but I have been down in the dumps these past few months. Actually, the money I am losing is about what you mentioned; roughly 1k a month less, for working harder at worse accounts than before
When things are changed at work, sure, we have to adapt. Some changes are minimal and really not that earth-shattering; but there comes a time when you have to say, enough is enough. Just think; many (if not most) people never hit that realization that they could do better, and end up at menial jobs until their dying day.
I applaud you for taking the bull by the horns and planning on making a way our for yourself.