Standard Role to Middleware (data exchange)

Hello

We have a SAP CRM Project where customer is very restrictive with authorizations management in productive systems .
We can’t assign a SAP_ALL   to connection user (RFCUSER)  for data exchange and we are trying to find a standard role pfcg with all necessary authorization in SAP CRM & SAP ECC to exchange master data & ERP customizing.
I’m worried about this because if I use a trace (ST01) to identify authorization objects I could create an incomplete role.
Does anybody have any information about this issue?  Do you Know a standard role to fullfil this security requirement?

Thanks in advance,

Pilar.