I finally got around to reading the debate when the House of Representatives approved an amendment to the National Defense Authorization bill limiting the size of the NSC staff to 100 people. [It's summer time, travel time, grandparent time.] The debate was brief; you can read it on pages H2677-79 of the Congressional Record for May 17.
Chairman Thornberry [R-TX] of the House Armed Services Committee drafted a particularly clever amendment, in my opinion. It does not forbid the president from having more than 100 staffers, but would require Senate confirmation of the national security adviser if that number were breached. The logic is that the staff is necessarily operational when above 100, but can remain solely advisory below that figure.
I'm torn. I strongly believe that the national security adviser should hold a Senate-confirmed position -- and should accordingly have some real authority to manage the interagency policy process for the president. I like forcing a presidential choice on the matter, as this amendment does. On the other hand, 100 is too arbitrary a number, and I can imagine shenanigans to stay under the cap. I also prefer front door approaches to the confirmation issue, rather than this side-door maneuver.
On balance, I'm glad the measure is in the House bill and I hope the Senate comes up with something similar -- and the White House compromises.