I don't think you get it.
Separating out the AMC and appraisal fee is not what Cost-plus is about. Separation can occur now, but it is not mandatory or typical.
The AMC & appraisal fee are both considered as a single cost in TRID (although they can be separated out, they represent a single charge to the consumer for a single service) and are currently included in the no tolerance bucket.
If appraisal fees are removed from that bucket, the AMC fee will still be set and still be reported; but not linked to the appraisal fee as it is now (which is why it can be combined as a lump sum).
Until appraisal fees are released from the zero tolerance bucket, the adaptation of the cost-plus model will likely never happen. For all the reasons I've posted, and for all the reasons you'll discover if you did some independent research on the matter.
You don't like the current system and want to change it; I get that.
But if you want to change it, don't you think it is worth some time and effort to understand how and why it works the way it does, so the solutions/changes you advocate for will address the specific issues in the current process, and once changed, will achieve the outcomes you desire?