Negotiation phase workflow customizations to emulate blanket sales orders

Hi - I am looking for feedback on anyone who has customized a unique NEGOTIATION workflow to emulate a blanket sale agreement process because the available attributes on the sales order are better than the blanket.

We would like to create a workflow to essentially Draft/Activate/Expire or Terminate.

The blanket sales order form was missing pricing visibility/application, sales team management, and several other additional field availability at the line level for us - so we are trying to create an agreement flow in the Negotiation phase of an order type that is Negotiation phase only.

Wondering if anyone else has done something similar, and if yes, any gotchas you experienced with the design?