One of the 'Rats organizational problems is that the ignorant racists in the Congressional Black Caucus gather copious amounts of seniority because their districts are rock solid 'Rat.
Consequently, if the 'Rats ever regain a majority in the House, they'll have to deal with a cadre of pompous ignoramuses in line to chair every committee in sight.
As I recall, Pelosi encountered this very problem in 2006 and, rather than give Elijah Cummings the chair he was entitled to, they made him a part of leadership and gave him a limo and driver. For his part, Elijah was happy to stay on the plantation...
That was James Clyburn. When Pelosi was Speaker, that opened up the the Majority Leader and Whip positions, filled by Steny Hoyer and James Clyburn, respectively.
When Republicans took control of the House and demoted Pelosi, she regained the Minority Leadership and pushed Hoyer into Minority Whip, leaving Clyburn with no position. Therefore, they created the "Assistant Minority Leader" position for Clyburn.
There is no "Assistant Majority Leader" position.
-PJ