Firing Inspectors General

As a good government ("goo-goo") type, I'm perturbed by the president's removal of several IG's and acting IG"s.  But this piece  suggests there's not much Congress can do to stop such actions by a president.  IG's are executive branch employees and as such are subject to the president's authority.

I wonder: could we look to sports, the NFL, for a solution:  There the tension is between getting the call right and keeping the game flowing.  Could we give the president a couple get-out-of-jail cards per term--allow her to fire two IG's but no more?  Arguably this would permit the president flexibility but not too much.

I'm afraid what will happen when the administration changes: the new president will use the Trump precedent to fire the Trump-IG's and goo-goo norms will suffer further erosion.