Answer:
The six that most recently got axed are:
Eth (ð) The y in ye actually comes from the letter eth, which slowly merged with y over time. ...
Thorn (þ) Thorn is in many ways the counterpart to eth. ...
Wynn (ƿ) Wynn was incorporated into our alphabet to represent today's w sound. ...
Yogh (ȝ) ...
Ash (æ) ...
Ethel (œ)