My goal when doing this is to turn this into an all yearly expense job. $22,000 a year should do it.
Ah, so you're trying to be arebelspy, Junior, eh? The wrenches in this plan are many. Card cancellations, people not picking your card for their tradeline purchase, etc. I get what you're trying to do, but the cards need to age a certain number of years (varies by company) for them to even be accepted. Also, cards do tend to become "resting" for a number of reasons. From memory, I've got a cap one, a discover and BoA resting at one company or another for various reasons.
Also, just like with manufactured spending, you have to be ready for the whole gig to come crashing down. A new law or rule or method to govern AUs could come along and kill this whole thing. Think of when Redbird got killed for MS. You just find other ways to game the system.
I try to squeeze benefits from my cards. When I don't get a tradeline sold, I've been doing low card balance forgiveness with about 8 cards. Some of them are now on the new "young" card system with the old company. A $25 for 2 month sale beats $1 in gas a month in forgiveness.