Assign zero global "Privileged User" rights?

Im trying to get the perms sorted out correctly to these levels:

  1. Staff (internal users)
  2. Clients (our primary contacts for our clients who want to use RT to
    open/resolve etc Helpdesk tickets)
  3. Client End users (who will ask for help only)

So far, the best route seems to:

  1. Create a queue ClientX
  2. Create a Group ClientXStaff, add staff who work at said client to
    this group. It has expected permissions (Create, edit, delete, update,
    own, modify etc)
  3. Create a Group ClientXClientAccess. Add priv. accounts for our
    clients, give them, OwnTicket, ViewTicket, EditTicket (not ViewComment
  4. remove all global Privileged User rights except those that are
    acceptable for all clients to have (OwnTicket [maybe], ViewTicket,
    EditTicket perhaps…

My question is this:

Is there any harm in not having any System level privileges if you
instead define them for each queue/group?