Expand the Cost Source Type selections

Why have this limited to PO, Quote and Misc? Why don't you treat the field in the Cost Source table just like a Resource. Let the Admin create their own list of Cost Sources by creating a list. This makes it very customizable for each company and give use better control. It is not convenient to put everything other than POs or Quotes in Misc. For my company it would be better if I had for example "LTA", "Engineer Estimate", "ROM", "Commercial Pricing".... Thanks