If you look at the list of positions which can be used to meet the position of responsibility requirement for Star and Life, you will see that assistant patrol leader is not listed there.
A reader is involved in a large troop, but due to low participation from scouts it is difficult to have patrol leader elections and a youth led program.
This weekend our Venturing Crew did the Introduction to Youth Leadership Skills for Crews (ILSC). This course teaches Crew members basic leadership skills. There is a corresponding course for Boy Scout troops (ILST).